abidslakhotiaarts

INTERIOR DESINGNING NOTES by Asmitha kumari D

2009-03-22T05:16:00.001-07:00

BASIC BUILDING STRUCTURE:

Components of building: A building can be broadly divided into two parts

1) Sub structure, 2) super structure.

The portion of the building below the surrounding ground is known as “sub structure”.

The portion above the ground is termed as “super structure”

The components of a building can be broadly summarized as

1) Foundation, 2) Plinth, 3) Walls, 4) Columns, 5) Floors, 6) Doors, windows, ventilators, 7) Stairs, 8) Roof, 9) Building finishes, 10) Building services.

Foundation: It is the lowest part of a structure which provides a base for the super structure.

These term includes the position of the a structure below the ground level as well as the artificial arrangement of concrete blocks, pipes, rafts, grillage, etc,

Provided to transmit the loads of the structure including the dead weight of the structure itself to the soil below.

Purpose of foundation:

It is often misunderstood that the foundation is provided to support the load of the structure

Infact, it is a device to transmit the load of the structure to the soil below.

Foundation is provided for the following four purposes:

1. To distribute the weight of the structure over large area. So, as to avoid overloading of soil beneath.

2. To provide a leveled surface for building operation.

3. To take the structure deep into the ground and thus, increase its stability preventing over turning.

The provision of foundation is made in such away that the soil below the foundation is not stressed beyond it’s save bearing capacity. Depending upon the type of soil existing at site, its sate bearing capacities and the type of building which is required to be constructed, A structures may need shallow(not so deep) or deep foundation.

In case of load bearing walls the foundation could be in the form of spread footing.

For frame structure the foundation could be in the form of independent column footing.

Plinth: The horizontal projection of stone or brick provided at the base of the wall above ground level is known as “plinth”. It rises the level of the ground floor of the building above natural ground level is known as “plinth level”. With the aim of projecting the ground floor from rain water and other weather effects.

Walls: Walls are provided to enclose or to divide the floor space in desired pattern.

In addition walls provide privacy security and gives protection against sun, rain, cold and other adverse effect of weather.

The division of floor space varies according to the functions required to be performed in the building.

In a well planned layout, the wall divides the space in such a manner so as to achieve maximum carpet area and minimum area of circulation.

Walls are constructed by use of building units like bricks, stone, concrete blocks (hollow or solid)

The building units are bounded together with mortar in horizontal and vertical joints and the construction is known as “masonry”.

When bricks are used as building units it is known as “Bricks Masonry”.

When stones are used as building units it is known as “Stone Masonry”.

Walls can be broadly divided into two categories

1. Load bearing walls

2. Non load bearing walls

1. Load bearing walls: A walls designed to carry superimposed load from the floor and roof is termed as “L.b.w”.

2. Non load bearing walls: An n.l.b.w. on the other hand causes its own weight and is not designed carry any superimposed load from the structure. They are normally provided as the partition wall.

Columns: A columns may be defined as an isolated vertical load bearing member. The width of which is neither less than its thickness or more than four time its thickness.

Pier: Pier is a vertical load bearing member similar to a column except that it is bounded into load bearing walls.

At the sides to form an integral part an extends to the height of the wall.

A pier is introduced to increase the stiffness of the wall to carry additional load or to carry vertical concentrated load. Pier also strengthens the wall to resist lateral pressure without buckling.

Floors: floors are flat supporting elements of a building. They divide a building into different level there by creating more accommodation on a given plot of land. The basic purpose of a floor is to provide a firm and dry platform for people. And other items like furniture’s, stores, equipment, etc. floor is generally reforded to by its location. A floor provided for accommodation below the natural the ground level is termed as the basement floor. A floor immediately above the ground is termed as ground floor. And all other floor such as 1^st, 2^nd floor etc. are termed as upper floor. A floor basically consist of 2 parts namely

1. Sub floor, 2.Flooring.

The sub floor is the structural component of the floor which support all the loads (dead and superimposed) and flooring is covering layer of desired specification (cement –concrete, terrazzo, tiles etc) provided over the sub floor to serve as a finishing layer.

Door, Windows and Ventilators:

A door may be defined as a barrier secured in and opening left in a wall to provide usual means of access to a building, room or passage this can be termed as most contently used moving component in a building.

A door normally consist of two component namely

1. Door frame, 2. Door shutter.

The door frame is permanently help in position and fixed to the masonry of the opening with the help of hold fast or rawl plugs. Shutter is the moving part of the door. Doors are made out of material like wood, steel, aluminums, plastic, flexible, rubber etc. they can be side hung, sliding, folding, revolving, or rolling type. Depending upon the functioning requirements.

A window may be defined as an opening made in walls for the purpose of providing day light, vision, & ventilation. Similar to door a window has framed and one or more shutter. The shutters are normally fitted with glass or similar transparent material. The windows can be side hung, top or bottom hung, lowered type, pivoted, metal window, bay windows, dormer window, sky light window. The shutter can be fully glazed, paneled & glazed or fully paneled type.

Stairs: A stair may be defined as a structure comprising of a number of steps connecting one floor to another. The stair must be constructed in such a manner that it is safe and comfortable to use and it should be so located as to permit easy communication. Stairs may be made from material like timber, bricks, steel, reinforced concrete etc. The selection of a type of material to be used depends upon the aesthetical importance, funds availability and fine resistance qualities desired.

Roof: It is the uppermost component of a building and its main function is to cover the space below and protect it from rain, snow, sun, wind, etc. A roof basically consists of two components namely

1. The roof decking, 2. The roof covering

The roof decking is the structure component which supports the roof covering. A roof can be either flat, pitched or curved in shape. The choice of the type of roof is made keeping in view of the location of the building, weather condition, funds available and function and aesthetics requirement. The structural component or roof decking in case of pitch roof is generally a rest, in case of curve roof it is a shell or dome and in case of flat roof it is a flat slab. The roof covering or roofing which is provided over pitched roof could be in the form of tiles, states, A.C sheets, G.I sheets etc. In case of flat roofs, the roof covering is termed as terracing, which could comprise of a layout of varying thickness of material like lime concrete, mud phuska etc. the terracing serves dual purpose I.e. 1.of providing suitable slopes on the roof top for draining of rain water 2. Of acting as consultation layer for providing thermal comport of the users of the space below.

Footing: A foundation unit constructed in bricks work, masonry or concrete under the base of a wall or column for the purpose of distributing the load over a large area.

Loft: An intermediary floor space created by introduction of a slab between floor and ceiling of a room. Passage and wherever it is provide with maximum clear height of 1.5mt. For storage purpose only.

Parapet: A low wall or railing build along the edge of roof or a floor.

Mezzanine floor: An intermediate floor between two floor level above ground floor and at least one side of it should form an integral part of space floor.

Porch: A covered surface supported on pillars for the purpose of pedestrian or vehicle approach to the building.

Chajja or sunshades: A sloping or horizontal structural over hand usually provided over opening on external wall for protection from sun and rain.

External wall: An outer wall of the building not being partition wall even through a joining to a wall of another building and also means a wall abutting on an interior open space of any building.

Court yard: A space permanently open to the sky enclosed fully or partially by building and may be at ground level or any level within or adjacent to a building.

Partition: An interior non load bearing wall.

Storey: The position of a building included between the surface of any floor and the surface of the floor meant above it.

Drain: Line of pipes including all fittings and equipment such as manholes, inspection chambers, traps. Used for drainage of the building.

Drain shall also include open channel used for carriage of surface bottom.

Drainage: The removal of any liquid by a system constructed for their purpose.

Balcony: A horizontal cantilevered projection including a hand rail or balustrade to serve as passage or sitting out place.

Sill: It is the horizontal member of brick stone, concrete or wood provided to give support for the vertical member of a window. It is also employed for the purpose of shielding of rain water from the face of the wall immediately below the window opening.

Lintel: A horizontal member of stone, bricks, wood, steel, or R.C.C. uses to support the masonry or load above an opening.

Coping: Coping is a covering placed on the exposed top of an external wall. It is essentially provided to present seepage of water. The joints of the top most course of the wall. It may be of concrete, stone, bricks or terracotta.

Throating: It is a term applied to the groove that on the under side of a projection course of masonry in order to check the seepage of rain water from the under side of projection portion.

Cantilever: The projection of the beam which support the balcony.

BRICKS:

TECHNICAL TERMS:

Header: It is a brick or stone which lies with its greatest length at right angle to the face of the work. In case of stone masonry, header is sometime is known as “True stone”. The course of brick work in which all the bricks are laid as header is known as “header course”.

Stretcher: It is a brick or a stone which lies with its longest side parallel to the face of the work. The course of brick work in which all the bricks are laid as stretchers is known as “stretcher course”.

Course: A course is a horizontal layer of a bricks or stones.

Bed: This is a surface of a stone or a brick perpendicular to the line of a pressure. It indicates the lower surface of a brick in each layer of course.

Back: The inner surface of a wall which is not exposed is called “Back”.

Face: The exterior of a wall exposed to weather is known as “Face”. The material used in the face of the wall is known as facing.

Hearting: It is the exterior portion of wall between the face and back.

Joint: It is a junction of two or more bricks or stones. If the joint is parallel to the bed of brick or stones in a course. Then it is known as “Bed joining”. The joints which are perpendicular to the bed joint are known as “vertical joint”, “side joints”, “and joints”.

Bond: This is the method of arranging bricks. So, that the individual units are tied. (Bonded) together. Bonding is essential to eliminate continuous vertical joints both in body as well as the face of the wall.

Spalls: These are the chips of stones used for filling (The gaps between bricks) interstices in stone masonry.

Bat: It is the portion of brick cut across its width.

Frog: It is an indentation (depression) on the top face of a brick made with the object of forming a key for the mortar. This reduces the weight of the brick also.

Plinth: It is a horizontal course of stone or brick provided at the base of the wall above the ground level. It indicates the height of the ground floor level above the natural ground level. It protects the building from dampness.

Plinth Course: It is the top most part of the plinth masonry.

String Course: It is the horizontal projected course of masonry projecting from the face of the wall for shedding rain water of the face. It imparts an aesthetic appearance to the structure and is generally provided at every floor level.

Sill: Sill is the horizontal member of stone, concrete stone or wood employed for the purpose of shedding of rain water. From the face of wall immediately below the opening. It support to vertical member of a wooden frame.

Lintel: It is a horizontal member of stone, brick, wood, iron, or R.C.C used to support the masonry or load above an opening.

Jambs: These are the vertical sides of an opening for doors and windows. These may be plane or may be provided with to resist receiving the door frame or window frame.

Reveals: These are the exposed vertical surfaces left on the sides of an opening after the door or window frame is fixed in position.

Cornice: It is the projecting horizontal ornamental course near the top of the building at the junction of wall and building.

Blocking Course: It is the top most course of a stone masonry provided immediately above the corners to prevent the tendency of the cornice to over turn.

Buttress: It is the sloping or stepped masonry projection from a tall wall intended to strengthen the wall against the thrust of the roof.

Pier: It is a isolated vertical mass of stone or brick masonry to support beams, lintel etc.

Template: Pieces of stones placed under the end of the beam to distribute weight on to a greater area.

Corbel: It is an extension of one or more course of stone or brick from the face of a wall to serve as a support for wall plate.

Queen Closure: It is the portion of a brick obtains by cutting a brick lengthwise into two portions.

King Closure: It is the portion of a brick obtains by cutting of the triangular pieces between the centre of one end and the centre of one side.

Beveled Closure: It is the portion of a brick obtains by the whole length of the brick is beveled for maintaining half width at one end and full width at other end.

Shapes of bricks: Ordinary bricks are rectangular solids. But sometimes bricks are given different shapes to make them suitable for particular type of construction. Following are such few types of bricks.

1. Bull nose brick: A brick molded with a rounded angle is termed as a bull nose. It is used for a rounded quoin. The centre of the curved portion is suited on the long center line of brick.

2. Channel brick: These brick are molded to he shape of a gutter or a channel and they are very often glazed. These bricks are used to function as drains.

3. Coping brick: These brick are made to suit the thickness of walls on which coping is to be provided. Such bricks take various forms such as chamfered, half-round or saddle-back.

4. Cow nose brick: A brick molded with a double bull nose on end is known as a cow nose.

Bull nose Channel brick coping brick Cow nose brick

5. Curved sector brick: These bricks are in the form of curved sector and they are used in the construction of circular brick masonry. Pillars, bricks chimneys, etc.

6. Hollow brick: Wall thickness 20-25mm.

7. Paving brick:

Chequred brick

8. Perforated brick:

BRICKS MASONRY

It is united mass obtained by systematic arrangement of bricks and bonding them together with mortar. Bricks are a building unit of hard inorganic clay material of a size which can be conveniently handled.

Bricks can be use for various construction purposes and can be easily arranged in various shapes for most of the structures like foundation, walls, columns, buttress, retaining structures, window sells, coping, ornamental brick work, fire places. Tall chimneys, thresholds, steps, floors, arch, etc.

The strength of the brick masonry depends upon the quality of brick and type mortar used.

MORTAR:

Mortar is a pasty material formed by the addition of water mixer composed of an aggugate building material which may be handling with a trowel (thapi). The mortar unites the individual bricks together.

They are different types of mortars in used

1. Mud Mortar

2. Cement Mortar

3. Lime Mortar

4. Cement Mortar

5. Lime Surkhi Mortar

Mud mortar is used for temporary construction.

Cement mortar is used for permanent structures.

In order to select a suitable type of mortar for a given construction. We must know the type of desired finish. The magnitude and mortar of super imposed load.

The effect of the weathering agencies and the important of structures.

In different parts of country, bricks used as length varying from 15cm to 25cm width 9cm to 20cm and the height 5cm to 10cm. Hence separate specifications are available with different department. Indian stand institution has suggested a uniform brick size for the whole country these is popularly known as modular brick normal size of modular brick is 20x10x10cm and the actual size 19x9x9cm.

These bricks are economical to manufacture require less area for drawing.

Characteristics of a good brick:

1. The brick should be compacting homogenous free from holes, crack, air bubbles, flaws, and stone lumps.

2. It should be well burned.

3. It should produced good sound when collides with other brick.

4. It should have uniform colors.

5. It should be tough and hard.

6. It should have finish surfaces on all the sides.

7. Bonding is the process of arranging bricks with mortar to tie them together in the mass of brick work.

8. It should have minimum of vertical joints in any part of the work.

9. It shouldn’t be continuous in two successive courses.

Characteristics of brick bond:

The brick masonry should have the brick of uniform size and shape.

The length of the brick should be equal to the twice the width of the brick. (4.5+4.5=9”).

The use of the brick bat should be discouraged.

The vertical joints in the alternate courses should be vertically above each other.

The stretchers should be only used in the facing while hearting should be done in headers only.

Types of bonding:

1. Header bond

2. Stretcher bond

3. English bond

4. Double bond

5. Single bond

6. Garden bond

7. Facing bond

8. Dutch bond

9. Raking bond

10. zigzag bond

11. English bond

12. Brick on edge bond

13. Bonds in columns

14. Bonds at junctions and squint junction

STONES:

Building stones are obtained from rocks occurring in nature. It is estimated that 3/4^th of the land area of the globe is under lane by sedimentary rocks and remaining 1/4^th by igneous and metamorphic rocks. The various stone derived from these rocks are

Ø Principle stone from igneous rock are granite or basalt. And trap.

Ø Principle stones from sedimentary stones are sand stone, shale, limestone and lateride.

Ø Principle stones from metamorphic rocks are quartzite, shade, marble, schirt.

Properties of a good building stone:

A good building stone should posses such characteristics:

Ø High strength

Ø High durability

Ø Sufficient hardness

Ø High resistance would be a fire resistance

Ø Specific gravity

Ø Crystalline structure

Ø Low water absorption

Ø Facility for curving and dressing

Ø Weather resistance and better appearance.

Generally stones from igneous and metamorphic rocks are heavier and more durable than stones from sedimentary rocks.

Types and uses of building stone:

1. Granite: It is a very hard and durable building stone suitable for works of importance such as bridge equipments piers etc. where weight and durability are essential. It is not suitable for curving because of its crystalline structure. It is available in these places M.P, H.P, A.P, Maharastra, Assam, Bihar, West Bengle, Jammu and Kashmir, Orrisa, Gujarat, Punjab, Kerala, Rajasthan, and Mysore.

2. Basalt and Trappe: It is a very hard and tough compact and hence expensive in work. It is used in foundation of work usually but may be use for super structures also. It is not suitable for moldings. It is available in Maharastra, West Bengle, and M.P.

3. Sano Stone: It is very easy to dress and work. Extensively used in general construction work. It is available in Andobar Island, Kashmir, M.P, V.P, Rajasthan, and Gujarat.

4. Lime Stone: It is used for flooring roofing, paving. It is used for general building purposes and manufacturing. It is available in Bengle, V.P, Rajasthan, Bihar, Andobar Island, H.P, M.P, V.P, Punjab, and Gujarat.

LATTERIDE: The stone is wet and soft when quartzite and should not be used until season for a month or two for achieving hardness. It is then cutted into rectangular blocks.

QUARTZITE: Silicon sand stones under the effect of metamorphic action. It is a very dense and strong stone with stratified structure and crystalline structure but breaks up into irregular shapes. It is difficult to dress and work. Quartzite is used for rubbled masonry. And also as aggiviate for concrete.

SLADES: These are metamorphic laminated rocks with plane of cleavage along which they can be split into very thin slabs. Slades are used as flooring and roofing material. Harder varieties of slades are used for dado works. These are available in Bihar, Mysore, U.P, Madras, M.P etc.

MARBLE: It is a compact crystalline stone formed by metamorphic stone action. It is one of the strongest and most durable varieties of lime stone. It is obtainable in varieties of colors. Plane or mixed from white to black. It can be easily cutted and curved and takes a high polish. It is extremely suitable for ornamental superior type of building work. It is also suitable for flooring and veneer work. It is available in V.P, M.P, A.P, Rajasthan, Mysore, Gujarat etc.

Suitability of types of stone for engineering works:

Ø Compact sand stones and granite are suitable for building in manufacturing town.

Ø Granites are suitable for building situated for sea shore

Ø Granite and basalt are suitable for paving work

Ø Sand stones, compact lime stone and quartzite are suitable for railway ballast

Ø Compact sand stones are suitable for structure where fire resistance is main requirement.

FLOORING

The purpose of the floor is to provide a level surface capable of supporting the occupant of a building, furniture, requirement and sometimes internal partitions.

A floor must satisfy the following requirement

1. Adequate strength and stability.

2. Adequate fire resistance

3. Sound

4, Damp resistance

5. Thermal insulation

The floor resting directly on the ground surface are known as ground floor while the other floor of each storey situated above the ground level are known as upper floors.

Components of a floor:

A floor is composed of two essential components

1. Sub floor, base case or floor base

2. Floor connecting or simple flooring

The floor base is a structural component that supports the floor covering. Ground floors may either rest directly on the ground or may be supported a little distance above the ground. The floor supported directly on the ground are known as solid floors while the floors supported above the ground level are called suspended floors they are made of timber.

Materials of Construction

Materials used for construction of ground floor are

1. Cement Concrete

2. Lime Concrete

3. Stone

4. Bricks

5. Wooden blocks (for wooden flooring only)

FLOORING OF DIFFERENT MATERIAL

1. Mud and Murram Flooring:

These are used in low cost housing especially in villages. This flooring is cheap, easy to construction and easy to maintain. It has good thermal insulation due to which it remains cool in summer and fairly warmed in winter. Murram is also known as disintegrated rock floor. This flooring has practically the same properties as that of mud flooring.

2. Brick flooring:

Such flooring is used in economical construction where good brick are available. This flooring is essential suited to ware house, stores, go downs etc. well burnt bricks of good colors and uniform shapes are used. (Wire cut bricks are used for flooring).

3. Flag Stone Flooring:

Flag stone is an laminated sand stone available in 2cm-4cm thickness in the form squares (30cmx30cm, 45x45, 60x60.) or rectangular (45x60) this type of work is called paving. (Generally used in exterior landscaping)

4. Cement Concrete Flooring:

This is used for residential, commercial and even industrial building, since the moderately cheap, quite durable and easy to construct. Floor consists of two components 1) Base concrete 2) Topping a wearing surface.

5. Grantithic Finish:

In industrial building hard wearing surface 0’ is sometimes required. This can be achieved by applying grantithic finish over the concrete topping this finish consist of rich concrete made with very hard and tough quality course such as granite, basalt, quartzite etc. The thickness of finish may be minimum 25mm. When laid monolithically with the over hardened surface for public buildings such as schools, hospitals etc. The thickness of finish may be 13mm-20mm.

6. Terrazzo Flooring:

This flooring is another type of floor finish that is laid on the concrete topping. It is very decorative and has good wearing properties due to this it is widely used in residential buildings, hospitals, offices, schools, or other public buildings. Terrazzo specially purposed concrete surface containing cement and marble chips of different colors. The flooring is however bit expensive.

7. Mosaic Flooring: (Chips of stones)

It is made of small pieces of broken tiles of china glazed or of cement or of marble arranged in different pattern. These pieces are cut to desired shapes and sizes.

8. Tile Flooring:

It is constructed in the form of square hexagonal or other shapes. Made of clay (pottery) cement concrete or terrazzo. These are available in the different sizes and thickness. These are commonly used in residential places, offices, schools, hospitals and other public building as an attractive to terrazzo flooring specially where the floor laid quickly (ceramic: made of clay. Top covering is made of porcelain)

(Vitrified: whole tile is made of same material)

9. Marble Granite Flooring:

It is superior type of flooring used in bathrooms, kitchen, sanitary, temples etc, where extra cleanliness is an essential requirement. Usually in rectangular manner as that for concrete flooring.

10. Timber Flooring:

This flooring is used for parliamentary halls, dining halls, auditorium etc. They are not commonly used in residential buildings in India because timber flooring is also quite costlier. In hilly areas where timber is cheaply and readily available and where temperature drops very slowly. Timber flooring is the damp prevention this can be done by introducing the DPC layer below the flooring.

DPC- Damp proof course

(Fixing process: fixed with the help of groove).

11. Rubber Flooring:

It consists of sheets or tiles of rubber variety of pattern and color with thickness varying from 3-10mm. The sheet or a tile is manufactured by mining pure rubber with tiles such as cotton fiber, granulated cork or asbestos fiber. Rubber flooring are resistant and noise proof. However they are costly they are used in offices, public buildings.

12. Linoleum Flooring:

It is a covering which is available in rolls and which is spread directly on concrete or wooden flooring. This sheet is manufactured by mixing oxidized linseed oil in gum resins, pigments, wood flour, cork dust and other filler materials. Linoleum tiles are also available which can be fixed to concrete based or wood floor in different pattern. It can’t be used in bathroom, kitchens etc.

13. Cork Flooring:

This flooring is perfectly noiseless and is used in libraries, theaters, art gallery, board casting stations etc. Cork is the outer bark of the cork oak tree. Available in the form of the cork carpet and work tiles. They are available in various sizes, thickness and shades.

14. Glass Flooring:

It is a special purpose flooring used in circumstances where it is desired to transmit light to the basement from the upper floor. It is very costly and is not commonly used.

15. Plastic or polyvinyl chloride (PVC):

It is made of plastic called polyvinyl chloride fabricated in the form of tiles of different sizes and color shades; these are used in residential as well as non residential buildings. It is smooth and good looking but can be damaged easily when in contact with burning object. Available in 1mm, 2mm, and 3 mm. it is fire retardant.

Silicon Flour- (it is the apoxy) is a powder to dry soon.

White cement- observes dust.

Latierate (white cement only)-it don’t observes dust.

Apoxy- combination of glass thin layer (this can be done on marble to avoid to absorb anything).

GLASS:

Glass could be grouped according to the nature:

GLASS

1. Annealed 2.Toughened 3. Special

a) Sheet Glass Float glass Plate Bent Glass a) Textured

b) Mirror b) Pressed

c) Obscure Glass a) plain c) Perforated

d) Glass Blocks b) Heat excluding d) Glass Bricks

e) Pin Heat Glass c) Safety Glass e) Non-Reflective

f) Plain Glass d) Ultra violet f) Wired Glass

e) Mirror g) Shielding

f) Bulletproof Glass h) Soluble Glass

g) Value added glass i) Fiber Glass

h) Etched glass j) Figured Glass

i) Sand blasted k) Foam Glass

j) Glue clipped l) Stained or col.

k) Acid etched

l) ‘V’ grooming

Glass is made by melting in a furnace at a very high temperature. A mixture of pure sand Fodor and clay with some amount of broken glass and then casting the molten mass into moulds into required shape.

Glass is transparent and hard and its needs to be cut with a diamond edge. The cost of glass depends on two factors.

1. Process of manufacturing, 2. Sizes available

Manufacturing of Glass:

1. Collection of Raw material.

2. Preparation of batch – material should be made in powder.

3. Melting in furnace.

4. Fabrication- Giving shape.

5. Annealing- Cooling.

The glass is a mixture of number of metallic silicates one of which is usually an alkali metal.

Various varieties of glass have been developed in recent times for various purposes and today it is possible to make glass lighter than a cork, softer than cotton or stronger than steel.

The varieties of glass are being used in building industries for various purposes such as walls, ceiling, door, windows, bathroom fittings and furniture’s.

Properties of glass:

1. It is basically hard, transparent and translucent material.

2. The properties such as hardness, fusibility can be change according to their required.

3. It is not affected by ordinary chemical agents like air and water.

4. It is possible to welt pieces of glass by fusions (melting).

5. It provides electric insulation due to uncertain crystalline structure.

6. It absorbs, refracts or transmits lights depending upon the varieties for a particular use.

7. It is available in various colors and shapes.

8. It has no shape melting points. Not effected by weather or heat.

9. It can be fabricated into desired shapes and sizes by heating and cooling.

Kinds of glass:

1. Crown glass: manufactured by means of a blow pipe which is dipped into molten glass and then blown into a globular form which is than detach from the blown pipe which is than rotated on a flat disk until it is plotted out. This is generally convex used for glass tubes electrical bulbs.

2. Sheath glass or plain glass: This is made from blowing glass into a large hollow cylinder. These cylinders are later split longitudinally. This glass is used for windowpanes.

3. Plat glass: This is made by posing white hot molten glass over an iron table and holding it into a uniform thickness. Under a heavy metal roller. This is clear and stronger glass with few or more vitual distraction. This is used for large and small window panes. Mirror, showcases, shops, window displays etc.

4. Fluted or ritted glass: These is a wavy glass with corrugation. It is used where privacy is required light is not obstructed.

5. Wired or reinforced glass: This is basically plate glass with wire netting imbarded in it. It resists fire and doesn’t fall into pieces when fractured. It is used for fire resistance door and windows and skylight.

6. Ground or obscure glass: This is made either by grinding on one side of the glass or melting powered glass upon it. There is used where light is required without transparency.

7. Bullets prove glass: Used for jeweler’s show rooms, bank, wind, shutters of automobiles. This glass is made from at least 4 layers of glass and clear high-test plastic. This is a layer of plate glass joint by vinyl resin used for showcases, jewelers, casher booth etc.

8. Mirror: The other wise transparent surface is made reflect by laying a silver nitrate and ammonia which make a mirror.

9. Flint glass or potash lead glass: This type of glass is used for electrical bulb, optical lenses, table ware etc.

10. Hard glass or potash lime glass: this is used for making glass articles subjected to high temperature.

11. Pyrex glass or borosilicate glass: This type of glass is used in high quality laboratories apparatus and cooking utensils.

12. Common glass or bottle glass: these are used in making medicine bottles.

METALS

Choosing Metals: Its industrial requirement and hardness cool surfaces. Metal may not be seen as an oblivious choice for the home but in contemporary interiors. It is celebrated for those qualities.

Compare with other materials smooth metal finishes can provide pleasing contrast terms of colors, texture, and temperature adding to the sensual enjoyment of a space.

A metal has many uses in the field of construction and interior of home or commercial places etc.

From architectural element such as windows and staircases to kitchens and bathrooms fitting and all kinds of furniture’s and lighting.

Using metal like steel and aluminums to stair raiser, door, units, wall units and even ceiling (steel) create a very modern look or you can choose less commonly metals. Such as Zn, cu, or other surfaces and interior details.

From the environment point of view metal losses marks because of its high embedded energy. A redeemed fixture (good quality fixture) however is that, nearly all metal are recycled.

Metals are classified into two types 1. Ferrous and 2. Non ferrous.

1. Ferrous: These metal contain iron as their constituent and are obtained from iron ores which consists of compounds of irons, non metallic elements (sand, coal) and impurity such as carbon, manganese, phosphorous, silicon, sulphure). The crude impure iron extracted from iron ores is known as “pig iron”.

The properties of these three ferrous metals vary mainly because of its carbon percentage or carbon content in the metal.

2. Non Ferrous: These metals do not contain iron as their main constituent. Some of the non ferrous metal, such as aluminum, copper, brass, zinc, lead have limited use in the building industry.

Ferrous Metals:

Cast iron: It is manufactured by refining pig iron in cupola furnace old casting or scrap iron is sometimes added to improve the quality of cast iron, carbon content in cast iron varies from 1.7 to 4.5%. Cast iron can be readily distinguished from wrought iron. By its crystalline structure, by its want of ductility and its brittleness. Iron is the metal from which many alloys including steel are made and it is how generally used in modern building construction. Cast iron is so called because the molten iron is cast into moulds. It is strong and more resistant to corrosion than wrought iron. In home it is mostly used in bath tubs, fire bags, stove and some types of heavy duty pots and pans.

Cast iron is generally classified into three types:

1. Grey cast iron,

2. White cast iron,

3. Malleable cast iron.

1. Grey cast iron: It is softer and tougher than white cast iron and runs freely into moulds and can be machine. It is generally used for engineering works or ordinary castings.

2. White cast iron: It is very hard and brittle and is unsuitable for general casting into machine. It is mostly used for conversion of wrought iron malleable cast iron.

3. Malleable cast iron: It is annealed (raw) white cast iron from which some of its carbon has been extracted by heating to red hot which makes it stronger less brittle more malleable and ductile than ordinary cast iron. It is softer and tougher than grey cast iron. It is used for door hinges, pipe fitting, and hardware agricultural implements.

Properties of cast iron:

Cast iron is strong in compression. It is brittle and doesn’t observe shocks. When subjected to fire it fails suddenly without giving any warning. It cannot be welded easily or rolled. It cannot be punch like steel but it can be easily melted and cast into various shapes and machined. It melts at a temperature of about 2000deg faranite. It normally offers excellent resistance to corrosion as compared to any other ferrous metal. Cast iron is generally used for making water and seepage pipe, spiral staircases, manholes over rain water pipes, gutters, and sanitary fittings.

Wrought Iron:

It is the purest form of iron with low carbon content less than 0.15% it is made from white cast iron by removing most of the carbon, manganese, silicon, phosphorous, and sulphur. Instead by being cast, this iron is stretched, hammered and twisted when in a hot and semi molten state.

Wrought iron can be used to make gated, windows, balusters, balustrades etc.

It has a tradition image by appointing a skilled craft man. You can get a unique piece of a wrought iron for a specific location.

Properties of wrought iron:

It passes the important quality of toughness ductility and malleability.

It can be easily welded at a temperature of 900deg c and their melting point is above 1500deg f.

It can be bent, twisted when either hot or cold.

Wrought iron rusts more quickly than cast iron.

Wrought iron is replaced at present to a great extend by milled steel.

Steel:

A metal alloy, steel is a mixture of iron with small properties of other metals. Added to enhance the irons performance.

There are many different products made from it and like iron which to date as a strongly traditional image. Steel is the self curiously modern material. So long as it in a dry environment steel should not corrode (become holes) and does not therefore need any special finish.

It can however be coated with paint or oil to seal it and exclude air that night damp (moist).

Steel can also be galvanized or electroplated with zinc to avoid corrosion or coated with a mixture of elements including carbon and copper which create a superficial rusty layer and there by protect the steel venerate.

Steel mesh or steel can be used on walls, stair tread and raiser and to form walkways and clad areas of floor specially where there is heavy traffic, the sheet can be grided or brushed. Usually found in a commercial environment, steel diamond plate flooring brings a modern, industrial quality to living space.

Stainless steel:

Stainless steel is more popular for use in interiors as it doesn’t rust. An alloy containing 20% nickel and chromium as a smooth and shiny finish that is immensely appending. The area of the home in which stainless steel is most widely used is kitchen. Inspired by the streamline, utitarean appearance of professional kitchen.

Designers created a sleek modern for domestic ones.

As the material stainless steel is almost maintenance free, any stains or marks quickly disappear under the friction of a scrub.

Bathroom bases, bathtubs have followed kitchen sinks and units though these are still expensive, exclusive items.

Steel is an alloy or compound of iron and carbon in the form of carboide of iron. The smaller the amount of carbon steel contained, the nearer will be its properties resembling those of wrought iron and greater the amount of carbon it posses nearer it will be approaching in properties to that of cast iron (0.25-1.25).

Properties of steel:

Steel are highly elastic, ductile, malleable, and wieldable. Steel is also flexible at a lower temperature than wrought iron steel have much higher compressive strength than wrought iron, steels are generally used for the following purposes:

1. As structural material in frames beams and light frames in the form of various sections.

2. As nonstructural component is used for grills, stairs, balustrade, windows and doors furniture’s etc.

3. Sanitary fittings.

4. Mechanical service in the form of steel pipes, tables, banks.

NON-FERROUS METALS:

1. Aluminum:

It is bluish, silvery, white lustrous metal obtained from bauxite ore, pure aluminum is very soft and ductile and therefore it is alloyed with other. Metals like copper, magnesium, silicon, manganese etc. which increases its strength and hardness while retaining its characteristic of lightness and durability. Aluminum is highly resistance to corrosion and very good conductor of heat and electricity, its melting temperature is 658deg c. this light weight metal is associated with aircraft and the wheels of sprat’s car. In its iodized form aluminum is porous unlike steel or iron, aluminum resells rusting and is therefore a useful material for windows. Its light weight makes it ideal for cleaning surfaces both horizontal and vertical sheeting can have a simple brushed finish or can be embossed with geometric pattern. Both tiles and sheets can be used to make a light weight floor covering which levels an element of modernity to an interior. There are also a number of designers or light weight chairs or tables and most of door furniture are made from aluminum. It is also used for post panels and balustrade, partitions and for general purpose such as foils, wires.

2. Lead:

It is bluish grey in color with silvery luster when freshly cut. It is obtained from sulphide ore of lead. Lead is a very soft, highly ductile, malleable and non corrodible metal with low fusion point and very low strength. This metal is extremely resistant to atmospheric. Corrosion and is not effected by soil or industrial waste.

Uses: It is used for several purposes like lead sheets for roofing, water services pipes, and soil and gas pipes and for general purposes such as lead oxide for paints making bullets, alloys etc.

3. Copper:

It is attracted by melting coppery rifes (it is an ore of copper). Pure copper is of lustrous red colors and is intensively used for engineering purpose. It is a light strong, ductile and malleable metal with good properties of resistance to corrosion in dry air. It can be forced or rolled or otherwise worked hot and cold and join into wires. It is a good conductor of heat and electricity.

Uses: copper is used for several purpose such as electric wires and cable sheet for roofing, lighting, protective devices, light gauge tubing for hot and cold water supply gas and sanitation services for general purpose such as protective coating for metals electroplating etc.

When it is new copper has a distinctive reddish oranges grow. The metal has a long life easy to work with and has a long uses such as wiring and piping. Copper can be used in kitchen like copper sheeting on the fronts of kitchen units. In the same way other metals and array of copper pans hanging from a rack gives a sticking visual appeals. In out doors copper reacts over times with carbonic acid in rain to acquire the distinctive green corrosion which looks attractive on cladding and roofing.

Brass:

It is an alloy of copper and zinc but various alloys are produced by varying the proportion of these metals and even adding minor proportion of other metals, properties of brass vary considerably by changing these proportions, most commercial brass are ductile and malleable at ordinary temperature and can be rolled into wires or last into moulds. Although colors are bright yellow when fresh but requires regularly cleaning.

Uses: Brass is used for several purposes such as fitting for doors and windows, stairs, grills, and finished hardware in buildings bearings for machinery. House hold utensils, furniture etc.

4. Bronze:

It is alloy of copper, zinc and tin and contains about 80% of copper. They are stronger and superior to brass for corrosion resistance properties. It is difficult to work with bronze and it is expensive.

5. Zinc:

Zinc is a malleable food safe metal. It is traditionally time on the counters of French bars. This metal is soft and abraded by use and so develops an attractive layer. When it is new zinc shade is bright and silvery its softness means the zinc can easily be folded, soldered and pinned over the surtales and around the counter tables, counter top and doors of kitchen units.

Tin: Metallic tin is found to occur in grains intermingled with gold ores of Bolivia, Guinea and Siberia. It is also available in nodules, which are known as ‘stream tin’. The chief of tin ores are tin stones, Stagnates, The Pyrites.

Uses: plating, lining lead pipes. Preparation of alloys and solder. Making evaporation basins, infusion pots etc. it is also used for giving protection coating to copper and iron utensils.

TIMBER:

Timber and its products:

The use of wood is a universal phenomenon. It marks a stage in a civilization of mankind since the dawn prehistoric civilization to the present days.

Wood is used in variety of ways:

Ø Man started his activities in the field of construction with the help of wood.

Ø Later on he made house hold articles, furniture’s, agricultural vehicles, ships and boats, dwells of gods etc. of woods.

Ø The worship is common through out the world.

Besides Asia, it is invoked in some parts, of Africa and laten America.

They are the symbols of prosperity which has been accepted by most of the Indian religion that is why we find a large number of trees motive in Hindus and jains, art and architecture.

Ø Wood as material for construction has been in use since the prehistoric period.

Ø This is proved by large number of exaction.

Ø Wood efforts large slope of decorative art.

Hence, during the historic period. We find large number of beautiful palaces and public building made of wood.

Ø Megasthenes is the Greek ambassador in pataliputra give a picturesque age of chandragupta mauria.

Ø A large place having evidence of the use of wood on large scale was unearthed during excavation at patliputra.

Ø At some places stone pedestals had socitts for the well decorated wooden posts, and at the others chair post, rafters, and lintels of wood were discovered.

Ø Recently the planes of the house of the satavahanas have been prepared with the help of data from excavation at parthon (Greece), bramapuri etc. From their it is evident that the houses were constructed in brick and mud and the roofs are made of tiles fixed on wooden frame. These frames are consisted of wooden rafters and porcelain. Supported by vertical pillars. These rafters are fixed on the top of the walls and covered by terracotta tiles.

Ø Secondly the door and windows were naturally made of wood as compared to stone. As a material of architectural and decorative art wood is easily available.

Ø Smooth and curve able wood on other hand has certain limitation on its use in construction and decoration.

Ø Stone is massive hard and requires great skill to fashion ate or decorate. Comparatively, stone work is more expansive and time consuming. Again, one has to face the problem weight of the structure and its balancing.

Ø During the early face architecture wood was preferred to stone. Despite the good qualities of wood there are certain limitations on the use of wood. Even it is desired well.

Ø Wooden construction doesn’t last for more than two to three centuries. Hence we find that usually the state and public structure are constructed by stone while less building are constructed with maximum use of wood.

Ø Timber being a natural product of India is available leaf and post, cub boards, shelf’s, etc.

Ø Strength characteristics of various types of timber vary one another. Timber generally use in India are bubble, Sal wood, teak wood, blue pine, walnut, deodar, chil, neem, mango, kail, etc.

Generally, the tree from which the timber is obtained is classified in

1. Exogenous, 2. Endogenous.

1. Exogenous: These are the outer growing trees. Trees which include all commercial timbers used for building purposes

2. Endogenous: These are the inner growing. Trees includes such as palm, bamboo. Which are not suitable for engineering view and are found in the tropics

The exogenous trees are divided into hard wood and soft wood.

Hard wood: It has broad leaves and generally dense and narrow, well defined annual rings. They are heavy, strong and hard. They are capable of resisting all stresses equally.

Soft wood: It have long and narrow pointed leaves and characterized by annual leaves which has straight grains more uniform texture and light color. It is very strong for direct pull but weak in resisting sneer.

Structure of Timber:

Bark or Spin: It is the outermost portion of the rings. The outer bark protects the tree from the high temperature and mechanical harm. The inner bark covering the cambium layer protects it from any injury.

Cambium Layer: This layer of sap between inner bark and sap wood is known as ‘cambium layer’. These layers marks bark on the outer side and root on the inner side.

Sap wood: The outer annual rings between cambium layer and heart wood are known as sap wood. It is usually light in color and weight. When compare to heart wood. Sap wood is not used for any engineering work it contain large amount of moisture and liable to quick decay.

Medullary Sheath: It is the layer between heart wood and the pith. It covers the pith from all around.

Pith or Medulla: It is the inner most portion of tree which is very soft portion and varies in size and shape for different types of tree. It consists entirely of cellular tissues.

Properties of good timber:

Strength: The timber should be strong enough to with stand the loads. Whether being applied slowly or suddenly. It should posses enough strength in direct compression and transverse direction.

Durability: A good timber should be capable of resisting the various actions due to the fungi, insects, chemical and mechanical agencies.

Whether resistance: A good timber should process adequate resistance against weather effect such as alternate drying and wetting alternate cooling and heating because of temperature variation.

Fire resistance: The timber should offer sufficient resistance against fire so that it doesn’t easily ignite. It helps in fire protection of buildings.

Elasticity: The timber should be capable of regaining its original shape when load causing deformation is removed. This property is important when timber is to be used to carriage shafts. Sports goods, wooden beams, floors etc.

Word ability: The timber should be easily work able and shouldn’t clag (stuck). It should also be Capable of easily plainned or make smooth.

Toughness and aburation: A good timber should be capable of offering resistance to shocks due to vibration and shouldn’t deteriorate due to mechanical wear.

Other properties of good Timber:

Ø Timber should have sufficient weight. A timber with heavy weight is considered to be sound and strong.

Ø A structure of timber should be uniform hard and compact.

Ø Timber should have sufficient hardness like resistance against penetration.

Ø Timber should have favorable physical characteristic such as dark color, straight fibers, shining appearance, free from defects, swells, smells, good sound when stuck.

Defects of Timber:

Several natural defects occur in all kinds of timber depending upon soil on which they grow and climatic condition to which they subjected while growing. These defects should be avoided or removed as far as possible during conversion for use.

Heart wood:

These are the cracks or splits in the centre starting from pith extending in the direction of modularly rays in one or opposite direction towards sap wood, such defects are found in matured trees but sometimes. They may be caused by quick drying of central part of tree. If a tree nearly maturity is felled and left un-barked for a long time this defect is caused due to shrinkage of hard wood.

Star shakes: These are cracks of splits which extend from bark towards sap wood. This defect is caused when the tree is subjected to severe heat or frost during its growth. The width of these cracks or shakes is more at the outer end and reduces when they extends towards centre.

Cup shakes and Ring shakes:

These are formed by the rupture of tissues in a circular direction a cross section of a log usually along annual rings when the rupture extends only apart around. It is called as cup shakes and the whole way round or almost so it is called ring shakes. This defect is caused either due to unequal growth or due to sudden contraction of timber under atmospheric changes assisted by twisting action due to wind.

Radial Shakes:

These are similar to star shakes but occurs due to exposure to sun. when felled timber is placed for seasoning. These cracks are fine irregular numerous cracks or split run for a short distance from bark towards centre then follow the course of an annual ring and lastly go towards the centre radially.

Ring galls:

These peculiar curved swellings found on living or dead tree generally caused by the growth layer over the wound left after branches have been imperfectly cut off or removed.

Upsets or Ruptures:

These are ruptures of fibers wood caused due to some sought of impact injury or pressure. They are also caused due to unskillful felling and violent wing effect.

Twisted fibers or wandering hearts:

This defect is caused due to tree being twisted constantly in one direction by the force of prevalent wind. This wood is unsuitable for squaring or sawing and hence can be used for posts of poles in un sawn condition or for fuel purpose.

Wind cracks:

These are shakes or splits on sides of a bark of timber due to shrinkage of the exterior surface exposed to atmospheric agencies like sun, wind etc.

Knots:

These are the bases of branches or limbs which are broken or cur off from the tree. The portion from which the branch is removed receives nourishment from the stem for a pretty long time and it ultimately results in the formation of dark hard rings which are known as knots. As continuity of wood fibers is broken by knots. They form a source of weakness.

End Splits:

These are cracks extending from one face to another.

Dead wood:

Timber obtained from dead standing tree (i.e. after maturity) is known as dead wood. It is light in weight deficient in strength and reddish in color.

WOOD:

Types of Plywood:

Ply woods are available in different grades:

1. Commercial plywood

2. Waterproof plywood

3. Marine plywood

4. Shuttering plywood

5. Fire retardant plywood

1. Commercial Plywood: The most common plywood that is used in interiors especially for office and other commercial interiors. This is cheapest variety of plywood available. The problem with the commercial is warping and termites.

2. Waterproof Plywood: The panel boards are dipped in a tank full of waterproofing chemicals thereby sealing the pores and making it waterproof. These are used for wardrobes and other furniture, especially in residential interiors.

3. Marine Plywood: The panel boards are put in a vacuum chamber where chemicals are injected in the boards under pressure and kept in the chamber for 6 hours and then dried. These are used mostly in kitchen counters, toilets doors or outer doors where this plywood would not be destroyed by water.

4. Shuttering Plywood: This special grade of plywood can withstand water up o 30 days for shuttering for the slabs and columns where the concrete is used for 14-21 days.

5. Fire Retardant Plywood: The panels undergo dipping treatments through 6-12 types of chemicals in that many tanks and after drying they became fire retardant. This are used to lint the railway coaches, Bus, Lorries etc.

ADVANTAGES OF PLYWOODS:

a. As plies are placed at right angles to each other, expansion and shrinkage are comparatively very low.

b. They are available in a variety of decorative appearance.

c. They are available in large sizes.

OTHER TYPES OF BOARDS:

1. Chip boards

2. Agro boards

3. Cement boards

4. OSB boards

1. Chip Boards: Small pieces of wood are crushed into small particles and then pressed with resin to form boards. These are cheap but finishing is not good with this boards. These boards are not strong and cannot hold the screw for the long time. These are good for horizontal surfaces. These are also known as particles boards i.e. NOVOPAN, CHIP BOARDS.

2. Agro Boards: These boards are made up of agricultural waste, sugar cane waste (pulp). These materials are also crushed into minute particles and pressed into boards with resin bordering. These boards are not very strong and the screw holding capacity is not good. These are also types of particle boards and are also called as Medium Density Fiber Boards or MDF as they are made of fibers, used for horizontal surfaces, wall paneling. E.g.: ECOBOARDS. (Made of pulp), NUWUD (cotton waste) etc.

3. Cement Boards: Crushed particles of wood is bonded with cement and converted into boards. These are very strong and water resistant, can be used for outer walls, false ceiling, out doors roofing for gazebos, wall paneling in damp areas, etc. those being made in cement does not give good finishing when cut and a bit difficult to handle by the carpenters. E.g. BISON boards of NCL INDIA, HYD.

4. OSB Boards: These are oriented strand boards. These boards are made up of strands of wood, about 30mm-45mm long and oriented such they are in the form of alternate grains. This makes the OSB extremely handy to use, as the screw holding capacity is as good as the plywood. These are usually made in Germany and are used for roofing. Hence, they have excellent water proofing character and look very attractive. When used for doors, all they need is papering and a coat or two of hand spirit polishing and staining if necessary, because the soft wood strands make beautiful pattern on the surface.

5. Particle Boards: Chips obtained by crushing TW (Timber wood) are seasoned are mixed with phenol. Formaldehyde and synthetic resin and spread on a plate in three layers. The middle layer contains thick chips while the outer ones contain thin chips. Nova pan uses urea and formaldehyde while Indian plywood uses only formaldehyde.

VARITIES OF TIMBER FOUND IN A.P:

Bamboo: It is an endogenous tree. It is flexible, very strong and durable. It is used for scaffolding, thatched roofs, rafters, temporary bridges, fancy goods etc.

Rose Wood or Black Wood:

It is dark in color. It is strong, tough and close-grained. It is handsome and it takes up a high polish. It maintains its shape well. It is available in large sizes. Its weight after seasoning is about 7900N/M3. It is used for furniture of superior quality, cabinet work, ornamental carvings, etc.

Teak Wood: Characteristics of teak wood are golden to dark brown, reddish brown, with a straight grain. Without protective finish, teak like most hardwoods exposed outdoors or in gardens environments. Will turn a silvery gray color. It is one of the world’s most naturally durable and stable woods. It is fire resistance. It can be easily seasoned and worked. It takes good polish; it is not attacked by white ants and dry rot. Its use is limited to superior work only as it is comparatively very costly.

Casuarinas: Its color is reddish brown. It grows straight. It is strong and fibrous. It is, however, badly twisted. It is used for scaffolding, posts for temporary structures, etc.

Tamarind: Its color is dark brown, it is knotty and durable. Its development is very slow. But it ultimately forms a massive appearance. Its fruits are also very useful. It is used for agricultural instruments, well kerbs, sugar mills, carts, brick moldings, etc.

Sissoo: It is also known as the shish or tail. Its color is dark brown. It is strong and tough. It is durable and handsome. It maintains its shape well. It can be easily seasoned. It is difficult to work. But it takes a fine polish. It is used for high class furniture, plywood’s, bridge piles, sport foods, railway carriages, etc. it is very good material for decorative works and carvings.

Banyan: Its color is red. It is soft and even grained. It is durable in moist places and under water. It takes a good polish. It is used for furniture, door panels, well kerbs, piles, railway sleepers, bridge construction, etc.

Pine: It is hard and tough except white pine which is soft. It decays easily, if it comes in contact with soil. It is heavy and coarse grained. The white pine is light and straight grained.

Palms: It contains ripe wood in the outer crust. The color of this ripened wood is dark brown. It is strong and durable. It is fibrous. It is used for furniture, roof covering, rafter, joists etc.

Mango: The mango tree is very well known for its fruits. Its color is deep grey. It is easy to work. It maintains its shape well. It is moderately strong. It is used for cheap furniture, toys, packing boxes, ship building, cabinet work, panels for doors and windows, etc.

Guava: It is fine grained. It is hard, tough and flexible. Its color is grayish brown. It is not very strong. It can be easily worked. It is used for making toys, handles of instruments, engraving work, etc.

Bijasal: Its color is light brown. It is coarse-grained, durable and strong. It is difficult to work. It is not easily attacked by white ants. It is used for ordinary building construction, cart wheels, etc.

CURTAINS

Furnishing and Upholstery (Window Dressing)

Ø Curtains

Ø Curtain Rod

Ø Pelmet (to cover the rod)

Ø Rings

Ø Tie backs or hold back

Ø Brackets

Ø Top Dressings

Ø C- Channels

Ø Tassels (Bunch of threads)

Ways

Ø Curtains

Ø Shades and Blinds

Ø Valences and Swags(top portion of the window)

Ø Accessories

Ø Hangings

Types of Curtains:

Ø Sash Curtain

Ø Café Curtain

Ø Smoke Curtain

Ø Plain Curtain

Ø Single/Double Curtain

Ø Pleated Curtain

Ø Tiered Curtain

Ø Long Curtain

Ø Top Rod Drapers

Ø Strap Curtain

Ø Sheer Curtain

Sash Curtain:

Plain Curtain:

Cafe Curtain:

Smoke Curtain:

Single/Double Curtain:

Pleated Curtain:

Tiered Curtain:

Strap Curtain:

Sheer Curtain:

Shower Curtain: It is made up of P.V.C

Fabric commonly used for curtains:

Ø Cotton

Ø Polyester

Ø Net

Ø Casement (khadhi)

Ø Linen

Ø Silk

Ø Satin

Ø Jute

Ø Jute Silk

Ø Cotton Silk

Ø Terry Voiles (lining cloth)

Ø Velvet

Ø Jacquards (sofas cloth)

Top Treatment of Windows:

Ø Valances

Ø Swag

Ø Cascade arrangement

Types of Swags:

Ø Wrapped

Ø Open

Ø Gathered

Ø Pleated

Ø Running

Types of Valences:

Ø Gathered

Ø Box Pleated

Ø Balloon Cloud

Ø Lambrequins

Swags:

Wrapped:

Open:

Gathered:

Pleated:

Running:

Upholstery- Cloth fixed to the furniture.

Furnishing- Cloths used on the furniture.

Blinds and Shades:

Blinds - P.V.C, Wood, or Canvas.

Blinds are calculated in Sq Ft.

Shades- Cloth is used. Lowered blinds.

Window Dressing:

CAPENTRY AND JOINARY:

Technical Terms:

1. Chamfering: Finish cutting for blocks.

2. Planning: To make the surface plane.

3. Plank: Sheet of wood.

4. Housing: Fixing into each other.

5. Screwing: Joining the portion with screws.

6. Rebating: Cutting and joining.

7. Beading: Thinner pieces of <3”. For decorative purpose.

8. Battern: Horizontal legends.

9. Veneering: Sticking the slice of wood.

10. Seasoning: Procedure of storage of wood.

11. Framing: Making a border limit.

12. Overlapping: To make one on the other.

Types of Joints:

1. Lengthing or Longitudinal: Join of two pieces horizontally.

2. Fishing:

3. Notching: Any joint done at 90deg beside each other, overlapped inside.

4. Angular: The joint at any

5. Housed: First portion is interested into the other. But still it will be visible at the equal level.

Dovetailed, tongue, Oblique, angular are load bearing

6. Dovetailed: For bridge, Furniture joint.

7. Framing: For door and windows.

8. Oblique shoulder: One thinner piece is inserted into the two pieces.

9. Butterfly: Pieces of battern joint with the help of metal strip or ledge.

10. Tongue or Grooved: One of the joint is inserted into other.

11. Widening and Side joint: Type of framing.

TYPES OF DESIGNING CONCEPTS:

Zen Style: More of Geometrical shapes (angles).

Victorian: More of Traditional things like chandeliers, fire place, glossy items, curving, and wood is used more and crystal.

Edwardian: Related to Victorian, glass, dark and harsh colors.

Traditional: Completely historic.

Indian (south and north): Mud, mirrors, silk, bandhi cloth, silver, terracotta. S.I- Brass, copper, greenery, and cotton mixed silk.

Chinese: Low level furniture, no curving, red color, dragons, crockery collection.

Japanese: Full height furniture’s, dark colors, candles etc.

Mughal Style: Golden, very more curving, silver articles, ceramic pots, heavy curtains, embroidery, natural stones, ceilings mirror, carpets.

Western: combination of steel and glass, bright colors, different textures, tiles flooring, cheeks and strips patterns, tertiary colors.

Modern: Leather, glass, steel, non colors and primary colors.

Contemporary: Present and traditional mix, heaviness less usage of material. Every space having usage.

Roman: Lamps and shades, full wall window, arches, rockery, bright colors.

French: Light colors with curving furniture, wooden flooring.

Country Side: More of natural things, greenery, stones, rustic effect ion, no polish, rugs, painted furniture, no silk.

The place above fire place is mantle piece.

The wall divides the paint with some biding is called “dado rail”.

TYPES OF LINES, LETTERING, AND DEMENSIONING:

The various types of lines used in engineering drawing are given below

1. Principal lines or outlines: Lines drawn to represent visible edges and surface boundaries of objects are called outlines. In geometrical drawings, these lines show the final shape of the required figures. They are continuous lines.

Pencil lines Ink lines

2. Dotted or dashed lines: Hidden edges are shown in a drawing by dotted lines. These lines are made up of short dashes of approximately equal length (about 1/8^th) and spaced at equal distance of about 1/32”. When a dotted line meets or intersects another dotted line or the outlines their points of meeting or intersection should be clearly shown.

3. Centre lines: Centre lines are drawn in the centers of figures which are symmetrical on two or all the four sides of their centers. They are usually extended about ½” beyond the boundary of the figure. They are composed of alternately long and short dashes, spaced approximately 1/16” apart. The short dashes are about 1/8” in length and the longer dashes about 6-8 times the short dashes. The points of intersection between two center lines must be clearly indicated.

4. Dimension lines: These lines are continuous but broken at a suitable place with sufficient gap for inserting dimensions. They are terminated at the outer ends by pointed arrow heads, partly filled-in and touching the out-lines or extension lines.

5. Extension lines: These are continuous lines. A gap of about 1/16” is kept between these lines and the out-lines of the drawing. They extend by about 1/8” beyond the dimension lines.

6. Construction lines: These lines are drawn for constructing drawings and they are shown in geometrical drawings only. They are continuous lines.

7. Section lines: These are continuous lines inclined at 45degree and spaced uniformly about 1/16” apart.

8. Cutting-plane lines: The location of a cutting plane is shown by a line made up of alternately a long dash and two short dashes in the ratio of about 8:1, the short dashes being approximately 1/8” long, with uniform gap of a bout 1/16” between them.

9. Border lines: These are continuous lines thicker than the outlines of a drawing.

Thickness and shade of lines:

In pencil drawings all lines are drawn thin. The outlines should be intensely black and they should form an outstanding feature on any drawing. The dotted lines should be black and all the other lines grey.

In ink drawings, the outlines are drawn thick, dotted lines of medium thickness and all the other lines thin, the ratio of their thickness being 3:1-5:1.

In this book, in addition to the above lines, other lines made up of alternately a dash and a dot, or a dash and two dots etc. have been drawn in some figures, merely to distinguish them from other lines.

Lettering: Writing of titles, dimensions, notes and other important particulars on a drawing. However accurate and neat a drawing may be drawn, its appearance is spoiled and some times its usefulness is impaired by poor lettering. Lettering should therefore be done properly in clear, legible and uniform style. It should be in plain and simple style so that it could be done freehand and speedily. Use of drawing instruments in lettering takes considerable time and hence it should be avoided. Efficiency in the art of lettering can be achieved by careful and continuous practice.

Single-stroke letters: These are the simplest form of letters and are usually employed in most of the engineering drawings. The word single-stroke should not be taken to mean that the letter should be made in one stroke without lifting the pencil. It actually means that the thickness of the line of the letter should be such as is obtained in one stroke of the pencil. The horizontal lines of letters should be drawn from left to right and vertical or inclined lines, from top to bottom.

Dimensioning: The detailed technique of dimensioning will be described are as follows:

1. Dimensions should be placed outside the views except when they are clearer and more easily readable inside.

2. Dimension lines should not cross each other.

3. Dimensions should not be shown between dotted lines as far as possible.

4. Dimension lines should be placed at least ¼” from the outlines and from one another.

5. Arrow head should be pointed and filled in. it should be about 1/8” long and its maximum width should be about 1/3 of its length. The arrow head is drawn freehand with two strokes made in the direction of the point and the space between them neatly filled up.

6. Dimension figures are inserted in the break provided in the dimension lines. They are usually placed perpendicular to the dimension lines, and in such a manner that they can be read from the bottom or right hand side. The dividing line of fraction is drawn in line with the dimension line.

COLOUR THEORY:

Topics

1. primary color

2. Secondary color

3. Sub-secondary color

4. Tertiary color

5. color wheel

6. Tints

7. Shades

8. Complementary color

9. Contrast color

10. Analogous color

11. Monochromatic color

12. Achromatic color

13. Greyish color

14. Neutral color

15. Warm color

16. Cool color

1. Primary colours: colours formed by themselves are formed in nature are called “primary colours”.

* Crimson red

* Lemon yellow

* Cobalt blue

2. Secondary colours: Mixing of any two primary colours. We get “secondary colours”.

*Red +Yellow = Orange.

*Yellow +Blue = Green.

*Blue+ Red = Voilet.

3. Sub-secondary colours: Mixing of primary colours in more or less quantity we get sub secondary colours.

*More of Red + Less of Yellow = Reddish Yellow

*More of Yellow + Less of Red = Yellowish Red

*More of Yellow + Less of Blue = Yellowish Green

*More of Blue + Less of Yellow = Bluish Green

*More of Blue + Less of Red = Bluish violet

*More of Red + Less of Blue = Reddish violet

4. Tertiary colours: Mixing of secondary colours we get tertiary colour

*Orange + Green = Olive Green

*Green + Voilet = Grey

*Voilet + Orange = Brown.

5. Colour wheel:

6. Tints: Adding more quantity of white to all colours (primary, secondary, sub-secondary, tertiary) we get tints.

*Red + White 1:1

*Red + White 1:2

*Red + White 1:3

Up to

*Red + White 1:7.

7. Shades: Adding quantity of black to all the colours we get shades.

8. Contrast/Opposite colours: Colours which are not present in the formation of secondary colour.

*Red *Green

*Yellow *Voilet

*Blue *Orange

10. Complementary Colours:

*Red *Green

*Reddish Yellow *Bluish

*Orange *Blue

*Yellowish Red *Bluish Voilet

*Yellow *Voilet

*Yellowish Green *Reddish Voilet

11. Analogous colours: Colours besides primary colours are Analogous

Colours.

R.V---R---R.Y

Y.R---Y---Y.G

B.G---B---B.V

12. Monochromatic Colours: Two tins and two shades of all colours we called monochromatic colours.

R+W 1:2

R+W 1:1

Red

R+B 1:1

R+B 1:2

13. Achromatic Colours: Grey colours tints and shades of group are called Achromatic Colours

G G G

+ R +

W E B

1:5 1:4 1:3 1:2 1:1 Y 1:1 1:2 1:3 1:4 1:5

14. Greyish Colours: Adding grey colour to primary, secondary colour

We get grayish colour.

Red + Grey = Reddish Grey

Yellow + Grey = Yellowish Grey

Blue + Grey = Bluish Grey

Orange + Grey = Greyish Orange

Green + Grey = Greyish Green

Voilet + Grey = Greyish Voilet

15. Neutral Colours: Adding tints of black to primary, secondary. We

get neutral colour

Red + Black Orange + Black

Yellow + Black Green + Black

Blue + Black Voilet + Black

16. Warm Colours: Shades of Red, Yellow, Orange

Red + Black

Yellow + Black

Orange + Black

17. Cool Colours: Colours starting from green to violet.

Green --- Bluish Green --- Voilet

Bluish Voilet --- Green.

PAPER- 1

1. Introduction to interior designing (purpose)

2. Design concept

3. Lines, lettering

4. Orthographic Projection ‘2d’

5. Metric Projection ‘3d’

6. Color theory, wheel

7. Carpentry and joinery

8. Types of kitchen

9. Doors and Windows

PAPER-2 (Materials)

1. Wood

2. Metal

3. Glass

4. Laminates, Ply wood

5. Tiles

6. P.O.P

7. Curtains

8. Paints

9. Carpets and rugs

10. Bricks

11. Upholstery

12. Hardware

13. Landscaping.

PAPER-3 (Services & Estimations) PAPER-4 (Particles)

1. Staircase 1. Concept Designing

2. Electrical Layout 2. Product “ “

3. A.C 3. Furniture “ “

4. Acoustics 4. Specification of material

5. Plumbing

6. Ceiling PAPER-5

7. Flooring. 1. Portfolio

2. Viva Voce.

Stones of India

2009-03-06T04:52:00.001-08:00

India possesses a wide spectrum of dimensional stones that include granite, marble, sandstone, limestone, slate, and quartzite, spread out all over the country.

India is also amongst the largest producer of raw stone material and the sector is quite developed and vibrant in the South, as well as in Rajasthan and Gujarat, with a dedicated resource of entrepreneurs. India also has an indigenous resource of machinery and tool manufacturers which cater well to the demands of this sector.

The Indian stone industry has evolved into the production and manufacturing of blocks, flooring slabs, structural slabs, calibrated - ready to fix tiles, monuments, tomb stones, sculptures, artifacts, cobbles, cubes, kerbs^{[disambiguation needed]}, pebbles and landscape garden stones.

Tradition of Stones

India's long history, dating back to 3200 BC has been influenced considerably by the disposition, development and use of stones and other construction materials. Dimension stones have also left deep imprints on the architectural heritage of the country. Innumerable temples, forts and palaces of Ancient Indian Civilization have been carved out of locally available stones. The Taj Mahal at Agra stands testimony to the age-defying beauty of Indian marble. Some of the ancient rocks cut wonders include Khajuraho Temple, Elephanta Caves, and Konark Temple. Besides, all major archeological excavations have revealed exquisitely carved statuettes and carvings in stone. Ancient Buddhist monuments like the Sanchi Stupa of 3rd century BC have also been carved out of stone.

This tradition of Stone Architecture has continued to the present era, with most of the important modern buildings in India like the Presidential House, Parliament House, and Supreme Court made from high quality sandstone of Rajasthan. The Bahá'í House of Worship of New Delhi stands testimony to the relevance of marble in modern Indian architecture.

Stones are still the mainstays of civil construction in India, with stones being used extensively in public buildings, hotels, and temples. It is increasingly being used in homes, with the use of stones now penetrating amongst the burgeoning middle class of India.

The success of commercial stone industry solely depends upon defects in rock/stone. Natural defects in ornamental/commercial rock deposits adversely affect the quality of rock deposit. Detection of natural defects in decorative and dimensional stone industry play vital role in the quality assessment.

India is pioneer in the exploration, mining of commercial rock deposits and in establishing a firm base for stone industry. India, with an estimated resource of about 1,690 million cu m, comprising over 160 shades of Dimension Stone Granites (DSG), accounts for about 205 of the world resources. Of the 300 varieties being traded in the world market, nearly half of them are from India. Commercially viable granite and other rock deposits are reported from Andhra Pradesh, Bihar, Gujarat, Karnataka, Madhya Pradesh, Maharashtra, Orissa, Rajasthan, Tamil Nadu, Uttar Pradesh, and others

Marble

Marble deposits are widespread in India, with deposits of economic importance being concentrated in the states of Rajasthan, Gujarat, Madhya Pradesh, Haryana, and Andhra Pradesh. Newer varieties are gradually being developed for economic exploitation in the states of Bihar, Jammu & Kashmir, Maharashtra, Sikkim, Uttar Pradesh, and West Bengal.

Rajasthan is the main depository of marble, with reserves spread over the districts of Nagaur, Udaipur, Rajsamand, Banswara, Dungarpur, Jaipur, Sirohi, Bhilwara, Ajmer, Bundi, Alwar, and Pali. The main varieties in Rajasthan include Green, Makrana Albeta White, Makrana Kumari White, Makrana Dungri White, Jhiri Onyx, Phalodi Pink, Ambaji White, Indo-Italian, Babarmal Pink, Bhainslana Black, Forest Green, Forest Brown, Agaria White, dan Morwar White.

Next to Rajasthan, Gujarat has vast reserves of marble in the districts of Banaskantha, Bharuch, Vadodara, Kachchh, and Panchmahal. Of these, Ambaji area in Banaskantha district and Chunchupura area in Vadodara district are the main quarrying centres for marble. Deposits of marble in Andhra Pradesh are spread over Guntur, Khammam, Cuddapah, Kurnool and Anantapur districts. Marble rocks of Bhedaghat, Katni, Majholi near Jabalpur in Madhya Pradesh are the latest discoveries.

Main states producing marble are Rajasthan, Madhya Pradesh and Gujarat

Rajasthan

The largest state of India accounts for over 90% of total marble production of the country. Main varieties here are:

Makarana Marble: The famous marble of which the Taj Mahal is made, it is highly calcic. Main sub-varieties are Kumhari, Doongri, Alberta, and Makaran White.The largest mines is Makrana marble.Length of mines is 1350m.
Rajnagar Marble: World's largest marble-producing area, with over 2,000 gang saw units located in the nearby town of Kishangarh to process the material produced. Agaria is the best variety of this area, with numerous other varieties and patterns, primarily in white base. The marble is dolomitic and often has quartz intrusions.
Andhi Marble: Located near the capital city of the state of Jaipur (also known as the 'Pink City'), it is dolomitic marble with intrusions of tremolite, and is commonly known by the name of pista (pistachio) marble, because of the green coloured tremolite against an off-white background. One of the famous varieties of this area was known as Indo-Italian, owing to its resemblance with Satvario Marble. Most of the mining of this famous field is now banned by the Supreme Court of India because of the vicinity of the area to the Sariska Tiger Reserve.
Salumber Marble: Also known as Onyx Marble, it has thick bands of green and pink hint. A resemblance to Onyx Marble from Pakistan gives it this name. This is also highly dolomitic.
Yellow Marble: Though it has not been metamorphosed and hence is still a limestone, it is known as Yellow Marble in trade circles. It is mined in the Jaisalmer District.
Bidasar: Again this is not marble, but is known as marble in trade circles. These are ultra basic rocks in shades of brown and green colour. The criss-cross linear pattern given it a remarkable resemblance to a photograph of dense forest. These are also known as forest green/brown or fancy green/brown.

Gujarat

Amba Ji Marble is one of the finest marble produced in India. It can be easily compared with Makarana Marble. It is highly calcic and is produced in a town called Ambaji (famous for its temple of Durga Devi). The marble has a very soft and waxy look, and is often used by sculptors.

Madhya Pradesh

Katni Range is famous for its beige coloured marble which is dolomitic but highly crystalline, with very fine grain size and some quartz intrusions. The marble accepts excellent polish. Another variety of the same range is red/maroon-colored marble.

'Jabalpur range' contains dolomitic marble of excellent whiteness. It is more often used as dolomite lumps for chemical and industrial uses.

Granite

India is endowed with one of the best granite deposits in the world, having excellent varieties comprising over 200 shades. India accounts for over 20% of the world resources in granite. Granite reserves in India have now been estimated by the Indian Bureau of Mines at over 42,916 million cubic metres. Splendid black and multicolour varieties of granite are available in the states of Karnataka, Andhra Pradesh, Tamil Nadu and Uttar Pradesh. Granite deposits are also widespread over the provinces of Rajasthan, Bihar, West Bengal, and Gujarat. India is the largest exporter of granite and granite products in the world.

Sandstone

Sandstone reserves in India are spread over the states of Andhra Pradesh, Assam, Bihar, Gujarat, Haryana, Madhya Pradesh, Meghalaya, Mizoram, Karnataka, Orissa, Punjab, Rajasthan, Uttar Pradesh, Tamil Nadu and West Bengal. Over 90% of the deposits of sandstone are in Rajasthan, spread over the districts of Bharatpur, Dholpur, Kota, Jodhpur, Sawai-Madhopur, Bundi, Chittorgarh, Bikaner, Jhalawar, Pali, and Jaisalmer.

Slate

Slate reserves in India are found in Rajasthan, Haryana, Himachal Pradesh, Andhra Pradesh, and Madhya Pradesh. Deposits in Rajasthan are spread over the districts of Alwar, Ajmer, Bharatpur, Tonk, Sawai Madhopur, Pali, Udaipur, Churu, and Chittorgarh.

Flaggy limestone

Kotastone of Kota district and Yellow Limestone of Jaisalmer district of Rajasthan are the prime limestone occurrences in India. Other deposits include the Shahabad Stone of Bijapur District and the Belgaum districts of Karnataka, Cuddapah Stone of Kadapa,Kurnool and the Anantpur & Guntur districts of Andhra Pradesh, Milliolitic Limestone from Saurashtra Region, Gujarat, and 'Yellow Limestone' of Kutch district of Gujarat, amongst others.

Limestone deposits in Andhra Pradesh, India

Andhra Pradesh has the privilege of possessing about 32% of the country's total reserves of limestone. Commercial grade limestone deposits are being exploiting from Bethamcherla, Macharla, Neereducherla, Tandur, Mudimanikyam of Kurnool, Guntur, Anantapur, Rangareddy, and Nalgonda districts are widely used in our country for panelling, and flooring purposes. Sullavai limestone of Karminagar and Warangal districts, massive limestones of Mudimanikyam, Nalgonda districts. Andhra Pradesh's limestone reserves are estimated about 30,424 million tonnes. Total India's limestones are estimated about 93,623 million tonnes. Limestones are extensively utilized for manufacturing of cement and also building stones, particularly flooring and roofing (Dept of Mines and Geology, AP,Venkat Reddy,2006).

Other dimensional stones

There are some other dimensional stones being quarried and used in consumption, in addition to the dimensional stones already detailed above. Laterite bricks are quarried in huge quantities and are utilised as bricks in the construction of houses and for pavements in the states of Orissa, Karnataka, Goa, and in other parts of coastal states. The felspathic sandstone occurring with the coal seams as overburden is also used as building stone. The huge deposits of basalt in the states of Maharashtra, Karnataka, and Gujarat are used as building stones since ancient times. Other quartzitic bands, occurring with phyllites and schists, are also utilised for building purposes. Khondelites from Eastern coast are being used widely in sculptures and as a building material. Felsite from Karnataka is being extensively used as a dimensional stone as well.

ROCK

2009-03-06T04:31:00.001-08:00

The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic. The scientific study of rocks is called petrology, and petrology is an essential component of geology.

Rock classification

Rocks are classified by mineral and chemical composition, by the texture of the constituent particles and by the processes that formed them. These indicators separate rocks into igneous, sedimentary and metamorphic. They are further classified according to particle size. The transformation of one rock type to another is described by the geological model called the rock cycle.

Igneous rocks are formed when molten magma cools and are divided into two main categories: plutonic rock and volcanic. Plutonic or intrusive rocks result when magma cools and crystallizes slowly within the Earth's crust (example granite), while volcanic or extrusive rocks result from magma reaching the surface either as lava or fragmental ejecta (examples pumice and basalt) .

Sedimentary rocks are formed by deposition of either clastic sediments, organic matter, or chemical precipitates (evaporites), followed by compaction of the particulate matter and cementation during diagenesis. Sedimentary rocks form at or near the Earth's surface. Mud rocks comprise 65% (mudstone, shale and siltstone); sandstones 20 to 25% and carbonate rocks 10 to 15% (limestone and dolostone).

Metamorphic rocks are formed by subjecting any rock type (including previously-formed metamorphic rock) to different temperature and pressure conditions than those in which the original rock was formed. These temperatures and pressures are always higher than those at the Earth's surface and must be sufficiently high so as to change the original minerals into other mineral types or else into other forms of the same minerals (e.g. by recrystallisation).

The three classes of rocks — the igneous, the sedimentary and the metamorphic — are subdivided into many groups. There are, however, no hard and fast boundaries between allied rocks. By increase or decrease in the proportions of their constituent minerals they pass by every gradation into one another, the distinctive structures also of one kind of rock may often be traced gradually merging into those of another. Hence the definitions adopted in establishing rock nomenclature merely correspond to selected points (more or less arbitrary) in a continuously graduated series.

English: Gabbro specimen; Rock Creek Canyon, eastern Sierra Nevada, California.

Sandstone

Banded gneiss

Impact on society

Rocks have had a huge impact on the cultural and technological advancement of the human race. Rocks have been used by Homo sapiens and other hominids for more than 2 million years. Lithic technology marks some of the oldest and continuously used technologies. The mining of rocks for their metal ore content has been one of the most important factors of human advancement, which has progressed at different rates in different places in part because of the kind of metals available from the rocks of a region.

The prehistory and history of civilization is classified into the Stone Age, Bronze Age, and Iron Age. Although the stone age has ended virtually everywhere, rocks continue to be used to construct buildings and infrastructure. When so used, rocks are called dimension stone.

Dimension stone

is natural stone or rock that has been selected and fabricated (i.e., trimmed, cut, drilled, ground, or other) to specific sizes or shapes. Color, texture and pattern, and surface finish of the stone are also normal requirements. Another important selection criterion is durability, the time measure of the ability of dimension stone to endure and to maintain its essential and distinctive characteristics of strength, resistance to decay, and appearance.

Quarries that produce dimension stone or crushed stone (used as construction aggregate) are interconvertible. Since most quarries can produce either one, a crushed stone quarry can be converted to dimension stone production. However, first the stone shattered by heavy and indiscriminate blasting must be removed. Dimension stone is separated by more precise and delicate techniques, such as diamond wire saws, diamond belt saws, burners (jet-piercers), or light and selective blasting with Primacord, a weak explosive.

Although a variety of igneous, metamorphic, and sedimentary rocks are used as dimension stone, the principal rock types are granite, limestone, marble, travertine, quartz-based stone (sandstone, quartzite) and slate. Other varieties of dimension stone that are normally considered to be special minor types include alabaster (massive gypsum), soapstone (massive talc), serpentine and various products fashioned from natural stone. ^[1]

The commonest finish mentioned below is polished. A polished finish is one having a surface with high luster and strong reflection of incident light (almost mirror-like). The rougher finishes are bush-hammered, honed, sandblasted, and thermal. A bush-hammered finish is one with a rough uniformly patterned surface produced by an impact tool. A honed finish is one with a superfine, smooth, satinlike, nonreflective surface. A sandblasted surface is one with an irregular pitted surface produced by impacting sand particles at high velocity against a stone surface. A thermal (or flamed) finish is one with a rough nonreflective surface with only a few reflections from cleavage faces, produced by applying a high-temperature flame. This finish may change the natural color of the stone. ^[2]

The most easily-accessible general references are the latest (2006) Minerals Yearbook Chapter (production and foreign trade, with statistics), and the latest (Issue 30) Dimension Stone Advocate News (new "building green" developments and demand statistics); see below.

Major applications

Rough cut slabs of granite dimension stone.

While common colors used in some of the major applications are listed below, there is an extraordinarily wide range of colours, available in thousands of patterns. These patterns are created by geological phenomena such as mineral grains, inclusions, veins, cavity fillings, blebs, and streaks. In addition, rocks and stones not normally classed as dimension stone are sometimes selected for these applications. These can included tiles made of jade, agate, and jasper.

Stone (usually granite) countertops and bathroom vanities both involve a finished slab of stone, usually polished but sometimes with another finish (such as honed or sandblasted). Industry standard thicknesses in the United States are 3/4" (2 cm) and 1.25" (3cm). Often 2 cm slabs will be lamintated at the edge to create the appearance of a thicker edge profile. The slabs are cut to fit the top of the kitchen or bathroom cabinet, by measuring, templating or digital templating. Countertop slabs are commonly sawn from rough blocks of stone by reciprocating gangsaws using steel shot as abrasive. More modern technology utilizes diamond wire saws which use less water and energy. Multi-wire saws with as many as 60 wires can slab a block in less than two hours. The slabs are finished (i.e., polished, honed), then sealed with resin to fill micro-fissures and surface imperfections typically due to the loss of poorly bonded elements such as biotite. The fabricators shop cuts these slabs down to final size and finishes the edges with equipment such as hand-held routers, grinders, CNC equipment, or polishers. There has been a recent (2008) hubbub about radon emission from granite countertops; the National Safety Council states that the contributions of radon to inside air come from the soil and rock around the residence (69%), the outdoor air and the water supply (28%), and only 2.5% from all building materials-including granite countertops. A concerned homeowner can employ radon mitigation and removal techniques the ASTM covers.^[3] The stone for countertops or vanities is usually granite, but often is marble (especially for vanity tops), and sometimes limestone or slate. The majority of the stone for this application is produced in Brazil, Italy, and China.

Slate tile covers this entire structure in Germany.

Tile is a thin modular stone unit, commonly 12 in. square (30.5 cm) and 3/8 in. (10 mm) thick. Other popular sizes are 15 in. square (38 cm), 18 in. square (46 cm), and 24 in. square (61 cm); these will usually be thicker than the 12 in. square. The majority of tile has a polished finish, but other finishes such as honed are becoming more common. Almost all stone tile is mass-produced by automated tile lines to identical size, finish, and close tolerances. Exceptions include slate flooring tile and special orders: tile with odd sizes or shapes, unusual finishes, or inlay work. In summary, the automated tile line is a complicated complex of cutting and calibrating machines, honing-polishing machines, edging machines that put on flat or rounded edges, and interconnecting conveyors to move the stone from the slab input to the final tile product. The stone for tiles is most commonly marble, but often is granite, and sometimes limestone, slate, or quartz-based stone. Common colors are white and light earth colors. Much of the stone for this application is produced in Italy and China.

Stone monuments include tombstones, grave markers or as mausoleums. After being gangsawed into big thick (up to 10 ft (3.0 m). long and over 6 in. thick) slabs, smaller saws or guillotines (they break the granite and make the rough edges commonly seen on monuments) shape the monuments. The fronts and backs are usually polished. The individual monuments are then carved, shaped, and further defined by hand tools and sandblasting equipment. The stone for monuments is most commonly granite, sometimes marble (as in military cemeteries), and rarely others. A rose quartz tombstone stands in a Harpers Ferry cemetery. Sandstone was common in the nineteenth century but is no longer used due to rapid rates of erosion. Most common monument colors for granite are gray, then black, then mahoghany; for marble it is white. Today, the majority of the stone used in North America in this application is imported from such countries as India and China. This has depressed traditional North American monument centres such as Georgia and Quebec.

Dimension stone has been used in the construction of buildings for centuries. Due to costs, today stone veneers are usually used in place of solid stone blocks. This courthouse was built of dimension stone quarried in Berea, Ohio.

There are a number of smaller applications for buildings and traffic-related uses. Building components include stone used as veneer (exterior), ashlar, or other shapes. Veneer is a nonload-bearing facing of stone attached to a backing, of an ornamental nature though it protects and insulates. Ashlar is a square block of stone, often brick-sized, for facing of walls (primarily exterior). The other shapes are rectangular blocks used for stair treads, sills, and coping (coping is sometimes nonrectangular). The shapes subject to foot traffic will usually have an abrasive finish such as honed or sandblasted. The stone is mostly limestone, but often is quartz-based stone (sandstone), or even marble or granite. Roofing slate is a thin-split shingle-sized piece of slate, and when in place forms the most permanent kind of roof; slate is also used as countertops and flooring tile. Traffic-related stone is that which is used for curbing (vehicular) and flagstone (pedestrian). Curbing is thin stone slabs used along streets or highways to maintain the integrity of sidewalks and borders. Flagstone is a thin naturally irregular-edged slab of stone, sometimes sawed into a rectangular shape, used as paving (almost always pedestrian). For curbing, the stone is almost always granite, and for flagstone the stone is almost always quartz-based stone (sandstone or quartzite).^[4]

There are several other applications resembling flagstone in using rough dimension (or crushed) stone, usually as quarried, sometimes made smaller (i.e. by a jackhammer), often simply put in place: dry stone and riprap.

The stone used in these applications usually has to have certain properties, or meet a standard specification. The American Society for Testing and Materials (ASTM) has such specifications for granite, marble, limestone, quartz-based dimension stone (C616), slate (C629), travertine (C1527), and serpentine (C1526).

Production

Marble quarry in Carrara, Italy.

The majors producers of dimension stone include Brazil, China, India, Italy, and Spain, and each have annual production levels of nine to over twenty-two million tons. Portugal produces 3 million tons of dimension stone each year.

According to the USGS, 2006 U.S. dimension stone production was 1.33 million tons valued at $265 million, compared to 1.36 million tons (revised) valued at $269 million in 2005. Of these, granite production was 428,000 tons valued at $105 million in 2006 and 416,000 tons valued at $106 million in 2005, and limestone was 559,000 tons valued at $96.1 million in 2006 and 581,000 tons valued at $95.8 million (revised) in 2005. The United States is at best a mid-level dimension stone producer on the world scene; Portugal produces twice as much dimension stone annually.^[8]

World comparison for dimension stone demand: The DSAN World Demand for (finished) Granite Index showed a growth of 15% annually for the 2000-2006 period, compared to 14% annually for the 2000-2005 period. The DSAN World Demand for (finished) Marble Index showed a growth of 12% annually for the 2000-2006 period, compared to 10.5% annually for the 2000-2005 period. Other DSAN indexes for 2007 (preliminary) indicate that the 2000-2007 growth probably will be down from the 2000-2006 growth. ^[9]

The DSAN U.S. Ceramic Tile Demand Index shows a growth of 5.0% annually for the 2000-2006 period, compared to 5.5% annually for the 2000-2005 period. The "traditional" major ceramic tile suppliers, Italy and Spain, have been losing markets to new entrants Brazil and China. The same thing has been happening with dimension stone with increasing supplies from Brazil, China and India.

The Chinese Government has made a policy shift of long-term worldwide significance for dimension stone production and demand by eliminating the 15% export tax rebate on all dimension stones. So far, it has not replaced it with an export tariff on it, as it has on other industrial minerals. In addition, the Chinese Government sometimes strongly discourages its domestic firms from buying rough dimension stone overseas.

"Building green" with dimension stone

Marble cladding on a building.

Green building or environmentally friendly construction with natural materials, is an idea that has been around for several decades. Energy price increases and the need for energy conservation when heating or cooling buildings have recently brought it to the fore. This resulted in the formation in 1993 of the U.S. Green Building Council (USGBC), which has developed a building rating system called Leadership in Energy and Environmental Design (LEED). Educational institutions (colleges, universities, grade, and high schools) are often requiring new buildings to be green, and a few jurisdictions (i.e., some cities) have some rules pushing green building. When "building green", dimension stone has a big advantage over concrete, aluminum, and steel, whose productions are all highly energy intensive and create much air and water pollution. As an entirely natural product, dimension stone also has an advantage over quartz surface artificial stone (resin-agglomerated stone) made from mixed quartz sand or ground stone and a resin (i.e., acrylic). Dimension stone rates very well in terms of the criteria on the ASTM checklist for sustainability of building products: there are no toxic materials used in its processing, there are no direct greenhouse gas emissions during processing, the dust created is controlled, the water used is almost completely recycled (per OSHA/MSHA regulation), and it is a perpetual resource (virtually inexhaustible in a human time scale). Dimension stone in use can last many generations, even centuries, so the dimension stone manufacturer haven't needed a product recycling program.^[10] One LEED requirement provides that the dimension stone used in a green building be quarried within a 500-mile (800 km) radius of the building being constructed. This gives a clear advantage to domestic dimension stone, plus some quarried near the U.S. borders with Canada and Mexico. A current problem is how to consider stone quarried domestically, sent to China or Italy for finishing, and shipped back to be used in a project. Dimension stone also has the advantage from a green perspective of being recyclable and can often be recycled and not sent to a landfill. There are also "green" ways of cleaning stone being developed; for example, removing the black gypsum crusts that form on marble and limestone by applying sulfate-reducing bacteria to the crust to gasify most of it, breaking up the crust. See DSAN for updates on "building green" and dimension stone recycling. ^[9]

The Federal Trade Commission (FTC) is reexamining and will probably update its "Green Guides" which it uses to regulate green advertising claims. The FTC's updating will emphasize green building, including the products it involves, such as dimension stone. When the new requirements are finalized, the FTC will go after firms that violate the new requirements, in order to establish legal precedents.

The Natural Stone Council has an extensive amount of information on building green with dimension stone, including a life-cycle inventory for each major dimension stone (i.e. granite, limestone), giving the amount of energy, water, and other inputs required per ton of stone extracted and produced, plus the amount of emissions to the air and water that occur during processing. Some best practice studies are available, for example, on water consumption, treatment, and reuse while extracting and processing dimension stone, including dust mitigation, sludge management, and maximizing water recycling.

Stone recycling and reuse

Reconstruction of the Charles Bridge in Prague showing numbered dimension blocks.

Recycling dimension stone can occur when structures are demolished, along with recycling timber and recycling construction aggregate in the form of concrete. The material most likely to be recycled is concrete, and this represents the largest volume of recycled construction material. Not too many structures incorporate dimension stone, and even less of them have dimension stone worth saving. Stone recycling is usually done by specialists that monitor local demolition activity, looking for stone-containing houses, buildings, bridge abutments, and other dimension stone structures scheduled for demolition. Particularly treasured are old hand-carved stone pieces with the chisel marks still on them, local stones no longer quarried or that are quarried in a different shade of color or appearance. There is no national or regional trade in reclaimed stone, so a large storage yard is required, since the recovered stone may not be quickly sold and reused. The recycled dimension stone is used in old stone buildings being renovated (to replace deteriorated stone pieces), in fireplace mantels, benches, veneer, or for landscaping (like for retaining walls).

The Parthenon in Athens underwent a major reconstruction prior to the 2004 Olympics.

Related to stone recycling and stone reuse is the deconstruction and reconstruction of a stone building. The building is taken apart stone block by stone block and the location and orientation of each block is carefully noted. Any roofing slate and interior stone in place is catalogued and moved in the same fashion. After transporting the blocks, slate, and other stone used to the new location, they are put back in place where and how they were originally, thus reassembling the building. This has been a very uncommon occurrence, but will probably become more common in the future.

Dimension stone is also reused. Buildings immediately spring to mind, but such things as the ornate stone walls, arches, stairways and balustrades alongside a boulevard can also be renovated and reused. Sometimes the old interior of the building is kept as is, after repair. Sometimes the old building is gutted, leaving only a shell or facade and the space inside reconfigured and modernized. The stone work will usually need attention too. ^[12]

The old stone work may only need cleaning or sandblasting, but it may need more. Firstly, the building exterior (facade) needs to be inspected for unsafe conditions.^[13] Next, the building walls need to be inspected for water leakages.^[14] The most likely needs are mortar restoration (repointing), applying consolidants to the old stone, or replacing pieces of stone that are deteriorated (damaged) beyond the point of any repair. The repointing is the removal of existing damaged mortar from the outer portion of the joint between stone units and its replacement by new mortar matching the appearance of the old.^[15] The consolidants re-establish the original natural bonding between the stone particles that weathering has removed.^[16] Deteriorated pieces of stone work are replaced with pieces of stone that match the original as much as possible. Exterior dimension stone will often change color after exposure to weather over time. For example, Indiana Limestone will weather from a tan to an attractive light yellow. Interior dimension stone can sometimes change its shade a little over time too. For both, it may not be possible to find an exact match, even from the original quarry. Stone will often change its appearance from location to location in the same quarry. If the dimension stone renovationist is truly fortunate, the original builder put aside some spare pieces of the stone for future need.

Stone selection and cleaning

The selector of dimension stone begins by considering stone color and appearance, and how the stone will match its surroundings. The selector has literally thousands of options to choose from, and should examine many options. In addition to many hundreds of different stones with different colors and patterns, each stone can change radically in color and appearance when a different finish is put on it. A polished finish accentuates the color and makes any pattern more vivid, and the rougher finishes (i.e. honed, thermal) lighten the color and make the patterns more subdued. With thousands of possibilities, the selector must start by looking at many stones in many different finishes, or photos of them. Such photos can be found on some dimension stone websites, and on DSAN's Architects Stone Selection Helper.

In addition to selecting a stone color and pattern, the suitability of its properties for the intended use must be considered. Stone being chosen for countertops or vanities should be nonabsorptive, resist stains, and be heat and impact resistant. Stone being used in tiles should be sealed in order to resist staining by spilled liquids. Stone being used for flooring, paving, or surfaces subject to foot or vehicular traffic ought to have a semiabrasive finish for slip resistance, such as bush-hammered or thermal. A glossy polished finish will be slick. Most flagstone surfaces are rough enough to be naturally slip-resistant. The ASTM document C1528 Standard Guide for Stone Selection is very helpful, and covers topics not mentioned here. ^[17]

Dimension stone requires some specialized methods for cleaning and maintenance. Abrasive cleaners should not be used on a polished stone finish because it will wear the polish off. Acidic cleaners can not be used on marble or limestone because it will remove (i.e. dissolve) the finish. Textured finishes (thermal, bush-hammered) can be treated with some mildly abrasive cleaners but not bleach or an acidic cleaner (if marble or limestone). Stains are another consideration; stains can be organic (food, grease, or oil) or metallic (iron, copper). Stains require some special removal techniques, such as the poultice method. A new method of cleaning stone on ancient buildings (midaeval and renaissance) has been developed in Europe: sulfur-reducing bacteria are used on the black gypsum-containing crusts that form on such buildings to convert the sulfur to a gas that dissipates, thus destroying the crust while leaving the patina produced by aging on the underlying stone. This method is still in development and not commercially available yet. The ASTM document C1515 Standard Guide for Cleaning of Exterior Dimension Stone is also very helpful, and covers problems and remedies not mentioned here ^[18]; if masonry, concrete or stucco walls are also involved

Marble

Marble is a nonfoliated metamorphic rock resulting from the metamorphism of limestone, composed mostly of calcite (a crystalline form of calcium carbonate, Ca C O₃). It is extensively used for sculpture, as a building material, and in many other applications. The word "marble" is colloquially used to refer to many other stones that are capable of taking a high polish.

Etymology

The word "marble" derives from the Greek μάρμαρον (marmaron)^[1] and that from μάρμαρος (marmaros), "crystalline rock", "shining stone"^[2]^[3], perhaps from the verb μαρμαίρω (marmairō), "to flash, sparkle, gleam"^[4]. This stem is also the basis for the English word "marmoreal" meaning "marble-like".

[edit] Origins

Marble is a metamorphic rock resulting from regional or rarely contact metamorphism of sedimentary carbonate rocks, either limestone or dolomite rock, or metamorphism of older marble. This metamorphic process causes a complete recrystallization of the original rock into an interlocking mosaic of calcite, aragonite and/or dolomite crystals. The temperatures and pressures necessary to form marble usually destroy any fossils and sedimentary textures present in the original rock.

Pure white marble is the result of metamorphism of very pure limestones. The characteristic swirls and veins of many colored marble varieties are usually due to various mineral impurities such as clay, silt, sand, iron oxides, or chert which were originally present as grains or layers in the limestone. Green coloration is often due to serpentine resulting from originally high magnesium limestone or dolostone with silica impurities. These various impurities have been mobilized and recrystallized by the intense pressure and heat of the metamorphism.

Types of marble

White marbles, like Carrara in Italy, Royal White and Beijing White in China and Malagori of Pakistan, have been prized for sculpture since classical times. This preference has to do with the softness and relative isotropy and homogeneity, and a relative resistance to shattering. Also, the low index of refraction of calcite allows light to penetrate several millimeters into the stone before being scattered out, resulting in the characteristic "waxy" look which gives "life" to marble sculptures of the human body.

Construction marble

In the construction, specifically the dimension stone trade, the term "marble" is used for any crystalline calcitic rock (and some non-calcitic rocks) useful as building stone. For example, "Tennessee marble" is really a dense granular fossiliferous gray to pink to maroon Ordovician limestone that geologists call the Holston Formation.

Marble is also used in coolers and kitchen construction because it stays 5°C (9°F) cooler than the air that surrounds it at room temperature and pressure.

Industrial use of marble

Colorless or light-colored marbles are a very pure source of calcium carbonate, which is used in a wide variety of industries. Finely ground marble or calcium carbonate powder is a component in paper, and in consumer products such as toothpaste, plastics, and paints. Ground calcium carbonate can be made from limestone, chalk, and marble; about three-quarters of the ground calcium carbonate worldwide is made from marble. Ground calcium carbonate is used as a coating pigment for paper because of its high brightness and as a paper filler because it strengthens the sheet and imparts high brightness. Ground calcium carbonate is used in consumer products such as a food additive, in toothpaste, and as an inert filler in pills. It is used in plastics because it imparts stiffness, impact strength, dimensional stability, and thermal conductivity. It is used in paints because it is a good filler and extender, has high brightness, and is weather resistant. However, the growth in demand for ground calcium carbonate in the last decade has mostly been for a coating pigment in paper.

Calcium carbonate can also be reduced under high heat to calcium oxide (also known as "lime"), which has many applications including being a primary component of many forms of cement.

Production

According to the United States Geological Survey, U.S. dimension marble production in 2006 was 46,400 tons valued at $18.1 million, compared to 72,300 tons valued at $18.9 million in 2005. Crushed marble production (for aggregate and industrial uses) in 2006 was 11.8 million tons valued at $116 million, of which 6.5 million tons was finely ground calcium carbonate and the rest was construction aggregate. For comparison, 2005 crushed marble production was 7.76 million tons valued at $58.7 million, of which 4.8 million tons was finely ground calcium carbonate and the rest was construction aggregate. U.S. dimension marble demand is about 1.3 million tons. The DSAN World Demand for (finished) Marble Index has shown a growth of 12% annually for the 2000-2006 period, compared to 10.5% annually for the 2000–2005 period. The largest dimension marble application is tile.

Artificial marble

Faux marble or faux marbling is a wall painting technique that imitates the color patterns of real marble (not to be confused with paper marbling). Marble dust can be combined with cement or synthetic resins to make reconstituted or cultured marble.

Cultural associations

As the favorite medium for Greek and Roman sculptors and architects (see classical sculpture), marble has become a cultural symbol of tradition and refined taste. Its extremely varied and colorful patterns make it a favorite decorative material, and it is often imitated in background patterns for computer displays, etc.

Places named after the stone include Marblehead, Ohio; Marble Arch, London; the Sea of Marmara; India's Marble Rocks; and the towns of Marble, Minnesota; Marble, Colorado; and Marble Hill, Manhattan, New York. The Elgin Marbles are marble sculptures from the Parthenon that are on display in the British Museum. They were brought to Britain by the Earl of Elgin.

cultured marble — marble powder with a binder.
faux marbling — painting surfaces to look like marble.
marble sculpture
paper marbling
Pietre dure — inlaying with marble and other stones.
scagliola—imitating marble with plasterwork.

Mississippian marble in Big Cottonwood Canyon, Wasatch Mountains, Utah.

Marble from Italy.

Black Dębnik marble portal (17th century) of St. Wojciech's Church in Kraków.

Blocks of cut marble at the historic mill in Marble, Colorado

Natural patterns on the polished surface of "landscape marble" can resemble a city skyline or even trees

wood

2009-03-06T03:07:00.001-08:00

Wood is an organic material; in the strict sense wood is produced as secondary xylem in the stems of woody plants, notably trees but also shrubs, etc. In a living tree it conducts water and nutrients to the leaves and other growing tissues, and has a support function, enabling plants to reach large sizes. Wood may also refer to other plant materials and tissues with comparable properties, and to material engineered from wood, or wood chips or fiber.

People have used wood for millennia for many purposes, primarily as a fuel or as a construction material for making houses, tools, weapons, furniture, packaging, artworks, and paper. Wood can be dated by carbon dating and in some species by dendrochronology to make inferences about when a wooden object was created. The year-to-year variation in tree-ring widths and isotopic abundances gives clues to the prevailing climate at that time.

Formation

A tree increases in diameter by the formation, between the existing wood and the inner bark, of new woody layers which envelop the entire stem, living branches, and roots. Technically this is known as secondary growth; it is the result of cell division in the vascular cambium, a lateral meristem, and subsequent expansion of the new cells.

Growth rings

Where there are clear seasons, this can happen in a discrete pattern, leading to what is known as growth rings, as can usually most clearly be seen on the end of a log. If these seasons are annual these growth rings are annual rings. Where there is no seasonal difference growth rings are likely to be indistinct or absent.

It is customary to make a distinction between two parts of a growth ring. The part nearest the center of the tree is usually composed of wider elements. It is almost invariably lighter in color than that near the outer portion of the ring. The inner portion is formed early in the season, when growth is comparatively rapid; it is known as early wood or spring wood. The outer portion is the late wood or summer wood, being produced in the summer.^[2] In white pines there is not much contrast in the different parts of the ring, and as a result the wood is very uniform in texture and is easy to work. In hard pines, on the other hand, the late wood is very dense and is deep-colored, presenting a very decided contrast to the soft, straw-colored early wood. In ring-porous woods each season's growth is always well defined, because the large pores of the spring abut on the denser tissue of the fall before. In the diffuse-porous woods, the demarcation between rings is not always so clear and in some cases is almost (if not entirely) invisible to the unaided eye.

Knots

Photo taken of a tree knot at the en:Garden of the Gods public park in Colorado Springs, Colorado (October 2006). Photo by Peter Rimar

A knot is a particular type of imperfection in a piece of wood, which reduces its strength, but which may be exploited for artistic effect. In a longitudinally-sawn plank, a knot will appear as a roughly circular "solid" (usually darker) piece of wood around which the grain of the rest of the wood "flows" (parts and rejoins).

A knot is actually a portion of a side branch (or a dormant bud) included in the wood of the stem or larger branch. The included portion is irregularly conical in shape (hence the roughly circular cross-section) with the tip at the point in stem diameter at which the plant's cambium was located when the branch formed as a bud. Within a knot, the fibre direction (grain) is up to 90 degrees different from the fibres of the stem, thus producing local cross grain.

During the development of a tree, the lower limbs often die, but may persist for a time, sometimes years. Subsequent layers of growth of the attaching stem are no longer intimately joined with the dead limb, but are grown around it. Hence, dead branches produce knots which are not attached, and likely to drop out after the tree has been sawn into boards.

In grading lumber and structural timber, knots are classified according to their form, size, soundness, and the firmness with which they are held in place. This firmness is affected by, among other factors, the length of time for which the branch was dead while the attaching stem continued to grow.

Knots materially affect cracking (known in the industry as checking) and warping, ease in working, and cleavability of timber. They are defects which weaken timber and lower its value for structural purposes where strength is an important consideration. The weakening effect is much more serious when timber is subjected to forces perpendicular to the grain and/or tension than where under load along the grain and/or compression. The extent to which knots affect the strength of a beam depends upon their position, size, number, and condition. A knot on the upper side is compressed, while one on the lower side is subjected to tension. If there is a season check in the knot, as is often the case, it will offer little resistance to this tensile stress. Small knots, however, may be located along the neutral plane of a beam and increase the strength by preventing longitudinal shearing. Knots in a board or plank are least injurious when they extend through it at right angles to its broadest surface. Knots which occur near the ends of a beam do not weaken it. Sound knots which occur in the central portion one-fourth the height of the beam from either edge are not serious defects.^[3]

Knots do not necessarily influence the stiffness of structural timber, this will depend on the size and location. Stiffness and elastic strength are more dependent upon the sound wood than upon localized defects. The breaking strength is very susceptible to defects. Sound knots do not weaken wood when subject to compression parallel to the grain.

In some decorative applications, to add visual interest, wood with knots is preferred.

The traditional style of playing the Basque xylophon txalaparta involves hitting the right knots to obtain different tones.

Heartwood and sapwood

A section of a Yew branch showing 27 annual growth rings, pale sapwood and dark heartwood, and pith (centre dark spot). The dark radial lines are small knots.

Heartwood is wood that has died and become more resistant to decay as a result of deposition of chemical substances (a genetically programmed process). It appears in a cross-section as a usually colored circle, usually following the annual rings in shape. Heartwood is usually much darker than living wood, and forms with age. Many woody plants do not form heartwood, but other processes, such as decay, can discolor wood in similar ways, leading to confusion. Some uncertainty still exists as to whether heartwood is truly dead, as it can still chemically react to decay organisms, but only once (Shigo 1986, 54).

Sapwood is the wood that is not heartwood. In the growing tree it is living wood. All wood in a tree is first formed as sapwood. Its principal functions are to conduct water from the roots to the leaves and to store up and give back according to the season the food prepared in the leaves. The more leaves a tree bears and the more vigorous its growth, the larger the volume of sapwood required. Hence trees making rapid growth in the open have thicker sapwood for their size than trees of the same species growing in dense forests. Sometimes trees grown in the open may become of considerable size, 30 cm or more in diameter, before any heartwood begins to form, for example, in second-growth hickory, or open-grown pines.

The term heartwood derives solely from its position and not from any vital importance to the tree. This is evidenced by the fact that a tree can thrive with its heart completely decayed. Some species begin to form heartwood very early in life, so having only a thin layer of live sapwood, while in others the change comes slowly. Thin sapwood is characteristic of such trees as chestnut, black locust, mulberry, osage-orange, and sassafras, while in maple, ash, hickory, hackberry, beech, and pine, thick sapwood is the rule. Others never form heartwood.

There is no definite relation between the annual rings of growth and the amount of sapwood. Within the same species the cross-sectional area of the sapwood is very roughly proportional to the size of the crown of the tree. If the rings are narrow, more of them are required than where they are wide. As the tree gets larger, the sapwood must necessarily become thinner or increase materially in volume. Sapwood is thicker in the upper portion of the trunk of a tree than near the base, because the age and the diameter of the upper sections are less.

When a tree is very young it is covered with limbs almost, if not entirely, to the ground, but as it grows older some or all of them will eventually die and are either broken off or fall off. Subsequent growth of wood may completely conceal the stubs which will however remain as knots. No matter how smooth and clear a log is on the outside, it is more or less knotty near the middle. Consequently the sapwood of an old tree, and particularly of a forest-grown tree, will be freer from knots than the inner heartwood. Since in most uses of wood, knots are defects that weaken the timber and interfere with its ease of working and other properties, it follows that a given piece of sapwood, because of its position in the tree, may well be stronger than a piece of heartwood from the same tree.

It is remarkable that the inner heartwood of old trees remains as sound as it usually does, since in many cases it is hundreds of years, and in a few instances thousands of years, old. Every broken limb or root, or deep wound from fire, insects, or falling timber, may afford an entrance for decay, which, once started, may penetrate to all parts of the trunk. The larvae of many insects bore into the trees and their tunnels remain indefinitely as sources of weakness. Whatever advantages, however, that sapwood may have in this connection are due solely to its relative age and position.

If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower. Since each succeeding ring is laid down on the outside of the wood previously formed, it follows that unless a tree materially increases its production of wood from year to year, the rings must necessarily become thinner as the trunk gets wider. As a tree reaches maturity its crown becomes more open and the annual wood production is lessened, thereby reducing still more the width of the growth rings. In the case of forest-grown trees so much depends upon the competition of the trees in their struggle for light and nourishment that periods of rapid and slow growth may alternate. Some trees, such as southern oaks, maintain the same width of ring for hundreds of years. Upon the whole, however, as a tree gets larger in diameter the width of the growth rings decreases.

Different pieces of wood cut from a large tree may differ decidedly, particularly if the tree is big and mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even-textured than that produced earlier, but in other trees, the reverse applies. This may or may not correspond to heartwood and sapwood. In a large log the sapwood, because of the time in the life of the tree when it was grown, may be inferior in hardness, strength, and toughness to equally sound heartwood from the same log. In a smaller tree, the reverse may be true.

Different woods

There is a strong relationship between the properties of wood and the properties of the particular tree that yielded it. For every tree species there is a range of density for the wood it yields. There is a rough correlation between density of a wood and its strength (mechanical properties). For example, while mahogany is a medium-dense hardwood which is excellent for fine furniture crafting, balsa is light, making it useful for model building. The densest wood may be black ironwood.

It is common to classify wood as either softwood or hardwood. The wood from conifers (e.g. pine) is called softwood, and the wood from dicotyledons (usually broad-leaved trees, e.g. oak) is called hardwood. These names are a bit misleading, as hardwoods are not necessarily hard, and softwoods are not necessarily soft. The well-known balsa (a hardwood) is actually softer than any commercial softwood. Conversely, some softwoods (e.g. yew) are harder than most hardwoods.

Wood products such as plywood are typically classified as engineered wood and not considered raw wood.

Colour

In species which show a distinct difference between heartwood and sapwood the natural colour of heartwood is usually darker than that of the sapwood, and very frequently the contrast is conspicuous. This is produced by deposits in the heartwood of chemical substances; these usually have no dramatic effect on the mechanical properties of the wood.

Some experiments on very resinous Longleaf Pine specimens indicate an increase in strength, due to the resin which increases the strength when dry. Such resin-saturated heartwood is called "fat lighter". Structures built of fat lighter are almost impervious to rot and termites; however they are very flammable. Stumps of old longleaf pines are often dug, split into small pieces and sold as kindling for fires. Stumps thus dug may actually remain a century or more since being cut. Spruce impregnated with crude resin and dried is also greatly increased in strength thereby.

The wood of Coast Redwood is distinctively red in colour

Since the late wood of a growth ring is usually darker in colour than the early wood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a finished surface as darker than the denser late wood, though on cross sections of heartwood the reverse is commonly true. Except in the manner just stated the colour of wood is no indication of strength.

Abnormal discolouration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discolouration is merely an indication of an injury, and in all probability does not of itself affect the properties of the wood. Certain rot-producing fungi impart to wood characteristic colours which thus become symptomatic of weakness; however an attractive effect known as spalting produced by this process is often considered a desirable characteristic. Ordinary sap-staining is due to fungous growth, but does not necessarily produce a weakening effect.

Structure

Wood is a heterogeneous, hygroscopic, cellular and anisotropic material. It is composed of fibers of cellulose (40% – 50%) and hemicellulose (15% – 25%) impregnated with lignin (15% – 30%).

In coniferous or softwood species the wood cells are mostly of one kind, tracheids, and as a result the material is much more uniform in structure than that of most hardwoods. There are no vessels ("pores") in coniferous wood such as one sees so prominently in oak and ash, for example.

The structure of the hardwoods is more complex.^[5] They are more or less filled with vessels: in some cases (oak, chestnut, ash) quite large and distinct, in others (buckeye, poplar, willow) too small to be seen plainly without a small hand lens. In discussing such woods it is customary to divide them into two large classes, ring-porous and diffuse-porous. In ring-porous species, such as ash, black locust, catalpa, chestnut, elm, hickory, mulberry, and oak, the larger vessels or pores (as cross sections of vessels are called) are localized in the part of the growth ring formed in spring, thus forming a region of more or less open and porous tissue. The rest of the ring, produced in summer, is made up of smaller vessels and a much greater proportion of wood fibres. These fibres are the elements which give strength and toughness to wood, while the vessels are a source of weakness.

Magnified cross-section of a diffuse-porous hardwood (Black Walnut), showing the vessels, rays (white lines) and annual rings

In diffuse-porous woods the pores are scattered throughout the growth ring instead of being collected in a band or row. Examples of this kind of wood are basswood, birch, buckeye, maple, poplar, and willow. Some species, such as walnut and cherry, are on the border between the two classes, forming an intermediate group.

Black locust end grain, showing the ring-porous structure.

If a heavy piece of pine is compared with a light specimen it will be seen at once that the heavier one contains a larger proportion of late wood than the other, and is therefore considerably darker. The late wood of all species is denser than that formed early in the season, hence the greater the proportion of late wood the greater the density and strength. When examined under a microscope the cells of the late wood are seen to be very thick-walled and with very small cavities, while those formed first in the season have thin walls and large cavities. The strength is in the walls, not the cavities. In choosing a piece of pine where strength or stiffness is the important consideration, the principal thing to observe is the comparative amounts of early and late wood. The width of ring is not nearly so important as the proportion of the late wood in the ring.

It is not only the proportion of late wood, but also its quality, that counts. In specimens that show a very large proportion of late wood it may be noticeably more porous and weigh considerably less than the late wood in pieces that contain but little. One can judge comparative density, and therefore to some extent weight and strength, by visual inspection.

The twisty branch of a Lilac tree

No satisfactory explanation can as yet be given for the real causes underlying the formation of early and late wood. Several factors may be involved. In conifers, at least, rate of growth alone does not determine the proportion of the two portions of the ring, for in some cases the wood of slow growth is very hard and heavy, while in others the opposite is true. The quality of the site where the tree grows undoubtedly affects the character of the wood formed, though it is not possible to formulate a rule governing it. In general, however, it may be said that where strength or ease of working is essential, woods of moderate to slow growth should be chosen. But in choosing a particular specimen it is not the width of ring, but the proportion and character of the late wood which should govern.

In the case of the ring-porous hardwoods there seems to exist a pretty definite relation between the rate of growth of timber and its properties. This may be briefly summed up in the general statement that the more rapid the growth or the wider the rings of growth, the heavier, harder, stronger, and stiffer the wood. This, it must be remembered, applies only to ring-porous woods such as oak, ash, hickory, and others of the same group, and is, of course, subject to some exceptions and limitations.

In ring-porous woods of good growth it is usually the middle portion of the ring in which the thick-walled, strength-giving fibers are most abundant. As the breadth of ring diminishes, this middle portion is reduced so that very slow growth produces comparatively light, porous wood composed of thin-walled vessels and wood parenchyma. In good oak these large vessels of the early wood occupy from 6 to 10 per cent of the volume of the log, while in inferior material they may make up 25 per cent or more. The late wood of good oak, except for radial grayish patches of small pores, is dark colored and firm, and consists of thick-walled fibers which form one-half or more of the wood. In inferior oak, such fiber areas are much reduced both in quantity and quality. Such variation is very largely the result of rate of growth.

Wide-ringed wood is often called "second-growth", because the growth of the young timber in open stands after the old trees have been removed is more rapid than in trees in the forest, and in the manufacture of articles where strength is an important consideration such "second-growth" hardwood material is preferred. This is particularly the case in the choice of hickory for handles and spokes. Here not only strength, but toughness and resilience are important. The results of a series of tests on hickory by the U.S. Forest Service show that:

"The work or shock-resisting ability is greatest in wide-ringed wood that has from 5 to 14 rings per inch (rings 1.8-5 mm thick), is fairly constant from 14 to 38 rings per inch (rings 0.7-1.8 mm thick), and decreases rapidly from 38 to 47 rings per inch (rings 0.5-0.7 mm thick). The strength at maximum load is not so great with the most rapid-growing wood; it is maximum with from 14 to 20 rings per inch (rings 1.3-1.8 mm thick), and again becomes less as the wood becomes more closely ringed. The natural deduction is that wood of first-class mechanical value shows from 5 to 20 rings per inch (rings 1.3-5 mm thick) and that slower growth yields poorer stock. Thus the inspector or buyer of hickory should discriminate against timber that has more than 20 rings per inch (rings less than 1.3 mm thick). Exceptions exist, however, in the case of normal growth upon dry situations, in which the slow-growing material may be strong and tough."^[6]

The effect of rate of growth on the qualities of chestnut wood is summarized by the same authority as follows:

"When the rings are wide, the transition from spring wood to summer wood is gradual, while in the narrow rings the spring wood passes into summer wood abruptly. The width of the spring wood changes but little with the width of the annual ring, so that the narrowing or broadening of the annual ring is always at the expense of the summer wood. The narrow vessels of the summer wood make it richer in wood substance than the spring wood composed of wide vessels. Therefore, rapid-growing specimens with wide rings have more wood substance than slow-growing trees with narrow rings. Since the more the wood substance the greater the weight, and the greater the weight the stronger the wood, chestnuts with wide rings must have stronger wood than chestnuts with narrow rings. This agrees with the accepted view that sprouts (which always have wide rings) yield better and stronger wood than seedling chestnuts, which grow more slowly in diameter."^[6]

In diffuse-porous woods, as has been stated, the vessels or pores are scattered throughout the ring instead of collected in the early wood. The effect of rate of growth is, therefore, not the same as in the ring-porous woods, approaching more nearly the conditions in the conifers. In general it may be stated that such woods of medium growth afford stronger material than when very rapidly or very slowly grown. In many uses of wood, strength is not the main consideration. If ease of working is prized, wood should be chosen with regard to its uniformity of texture and straightness of grain, which will in most cases occur when there is little contrast between the late wood of one season's growth and the early wood of the next.

Monocot wood

Trunks of the Coconut palm, a monocot, in Java. From this perspective these look not much different from trunks of a dicot or conifer

Structural material that roughly (in its gross handling characteristics) resembles ordinary, 'dicot' or conifer wood is produced by a number of monocot plants, and these are also usually called wood. Of these, bamboo, botanically a member of the grass family, has considerable economic importance, larger culms being widely used as a building and construction material in their own right and, these days, in the manufacture of engineered flooring, panels and veneer. Another major plant group that produce material that often is called wood are the palms. Of much less importance are plants such as Pandanus, Dracaena and Cordyline. With all this material, the structure and composition of the structural material is quite different from ordinary wood.

Water content

The churches of Kizhi, Russia are among a handful of World Heritage Sites built entirely of wood, without metal joints.

Water occurs in living wood in three conditions, namely: (1) in the cell walls, (2) in the protoplasmic contents of the cells, and (3) as free water in the cell cavities and spaces. In heartwood it occurs only in the first and last forms. Wood that is thoroughly air-dried retains from 8-16% of water in the cell walls, and none, or practically none, in the other forms. Even oven-dried wood retains a small percentage of moisture, but for all except chemical purposes, may be considered absolutely dry.

The general effect of the water content upon the wood substance is to render it softer and more pliable. A similar effect of common observation is in the softening action of water on paper or cloth. Within certain limits, the greater the water content, the greater its softening effect.

Drying produces a decided increase in the strength of wood, particularly in small specimens. An extreme example is the case of a completely dry spruce block 5 cm in section, which will sustain a permanent load four times as great as that which a green (undried) block of the same size will support.

The greatest increase due to drying is in the ultimate crushing strength, and strength at elastic limit in endwise compression; these are followed by the modulus of rupture, and stress at elastic limit in cross-bending, while the modulus of elasticity is least affected.

Fuel

Main article: Wood fuel

Wood is burned as a fuel mostly in rural areas of the world. Hard wood is preferred over softwood because it creates less smoke and burns longer. Adding a woodstove or fireplace to a home adds ambiance and warmth

Construction

Wood can be cut into straight planks and made into a hardwood floor (parquetry).

The Saitta House, Dyker Heights, Brooklyn, New York built in 1899 is made of and decorated in wood.^[8]

Wood has been an important construction material since humans began building shelters, houses and boats. Nearly all boats were made out of wood until the late 19th century, and wood remains in common use today in boat construction. New domestic housing in many parts of the world today is commonly made from timber-framed construction. In buildings made of other materials, wood will still be found as a supporting material, especially in roof construction, in interior doors and their frames, and as exterior cladding. Wood to be used for construction work is commonly known as lumber in North America. Elsewhere, lumber usually refers to felled trees, and the word for sawn planks ready for use is timber. Wood is also commonly used as shuttering material to form the mould into which concrete is poured during reinforced concrete construction.

Wood unsuitable for construction in its native form may be broken down mechanically (into fibres or chips) or chemically (into cellulose) and used as a raw material for other building materials such as chipboard, engineered wood, hardboard, medium-density fiberboard (MDF), oriented strand board (OSB). Such wood derivatives are widely used: wood fibers are an important component of most paper, and cellulose is used as a component of some synthetic materials. Wood derivatives can also be used for kinds of flooring, for example laminate flooring.

Wood is also used for cutlery, such as chopsticks, toothpicks, and other utensils, like the wooden spoon.

[edit] In the arts

Artists can use wood to create delicate sculptures.

Main article: Wood as a medium

Wood has long been used as an artistic medium. It has been used to make sculptures and carvings for centuries. Examples include the totem poles carved by North American indigenous people from conifer trunks, often Western Red Cedar (Thuja plicata), and the Millenium clock tower ^[9], now housed in the National Museum of Scotland^[10] in Edinburgh.

It is also used in woodcut printmaking, and for engraving.

Certain types of musical instruments, such as those of the violin family, the guitar, the clarinet and recorder, the xylophone, and the marimba, are made mostly or entirely of wood. The choice of wood may make a significant difference to the tone and resonant qualities of the instrument, and tonewoods have widely differing properties, ranging from the hard and dense (african blackwood used for the bodies of clarinets to the light but resonant European spruce (Picea abies)) traditionally used for the soundboards of violins. The most valuable tonewoods, such as the ripple sycamore (Acer pseudoplatanus), used for the backs of violins, combine acoustic properties with decorative colour and grain which enhance the appearance of the finished instrument.

interior notebook

2009-03-06T02:35:00.001-08:00

BASIC BUILDING STRUCTURE:

Components of building: A building can be broadly divided into two parts