CPCCBC4006A - Select, procure and store construction materials
for low-rise projects

 

Stone
Clay products
Concrete products
Lime silica bricks
Mortar
Timber products
Metals
Plaster
Glass
Plastics
Coatings
Adhesives
Sealants

Foundation Material

 

Foundation is the natural material on which the building rests. Generally base rock, especially of igneous origin, is the strongest foundation material.

 

          ̃ differentiate between Foundation and Footing

 

Foundation material is categorised in simplistic manner such as:

 

         ̃  IGNEOUS ROCKS                     (Granite-Basalt)

 

         ̃  SEDIMENTARY ROCKS         (Sandstone-Limestone)

 

         ̃  METAMORPHIC ROCKS       (Conglomerates -Marble; Slates)

                (Silts, Sands, Gravels, compressed into rock like masses)
Variety of rocks is great and varies with locations

 

Soil         ̃ is the loose material that results from the transformation of the underlying parent rock by more or less simultaneous interaction of climatic factors (sun, wind, rain, frost) and chemical changes, brought about by biological agents (flora and fauna) and migration of chemical substances through rain, evaporation, surface and underground water.

 

Gravel     ̃ Most gravels are a combination of coarse and fine particles of rock and sands. Stability of gravel is good if clay content is neglected. Usually good bearing capacity, and less prone to erosion than are sands.

 

Sand       ̃ composed of fine grains and hard minerals and considered as a cohesionless soil. A suitable foundation material, but  unprotected prone to erosion by wind action.

 

Sand dunes in waterfront locations, particularly near the ocean, provide very risky foundations..

 

Clay        ̃ expand and becomes plastic when wet, retains water and dries out very slowly. Clay is a cohesive soil and usually inadequate as foundation material because of the high degree of expansion and contraction between wet and dry conditions. When using as foundation consult soil-engineer about its suitability.

 

For specific building sites it is advisable to consult soil engineer to ascertain the subsurface materials and the levels at which they occur to make sure the foundation material is suitable for the proposed building.

Stone

The term ‘stone’ usually designates blocks or pieces of the basic material rock (refer to foundation material). It is one of the oldest building materials known to persons. Natural stone and soils have been used as building material  for more than 10000 years, and earth walling particularly has been formally tested, documented and accepted under some building codes and enjoys popularity in some countries.

Stone used for building purposes are generally classified according to the form in which it is available commercially:   1. rubble (fieldstone)           2. dimension (cut stone)     3. flag-stone (flat slabs)     4. crushed rock

Despite the abundance of rock, relatively few stones satisfy the requirements as building stones. The important requirements are:

1. strength,                          4. hardness,                 3. workability,     4. durability,        5. colour and grain

6. porosity and texture      7. ease of quarrying   8. accessibility.

Stone which does, in general, satisfy the foregoing requirements and which is commonly used in building include granite, limestone, travertine, marble, sandstone, and slate.

 

The process of removing stone from its natural bed is known as quarrying. The method of quarrying depends on the nature of the stone. The building industry today uses stone largely as a facing material for large buildings, but it is also used for loadbearing walls for two or three storey buildings.

 

Granite          ̃ a coarsely crystalline igneous stone. It is generally very hard, strong, durable, and capable of taking a high polish. Granite has a wide variety of uses in building, including flooring, interior and exterior wall facing, column and mullion facings, stairs etc.

 

Basalt          ̃, generally a fine grained crystalline igneous stone of dark grey to blue grey colour. It comes from volcanic origin, is very hard wearing, and used as crushed aggregates for concrete (blue metal).

 

Limestone   ̃ a sedimentary class of stone, the most widely used building stone in the world. Limestones are composed mainly of two basic ingredients calcium carbonate and magnesium carbonate, together with other elements in lesser amounts.

 

Sandstone  ̃ a sedimentary class of stone, like limestone, made up of silica grains cemented together. The cement may be silica, calcium carbonate, or clay. The hardness and durability of the particular sandstone depends on the type of cement.

 

Marble         ̃ an example of a metamorphic rock, one that has been changed from its original structure. Stone. in this case limestone and dolomite have been re-crystallised to form marble. The colours of marble range from pure white through all shades of grey to black, including violet, red, yellow, pink, and green. Marble can be carved or turned and brought to a high polish. It is used mainly wall panels, column encasing, paving slabs, stair threads, balustrades etc.

 

Slate              ̃ a metamorphic rock, formed by the metamorphosis of clay and shales which have been deposited in layers. A unique characteristic of the material is the relative ease with which it may be separated into thin sheets, called slates. Nowadays seldom used as roofing material but for flooring, interior and exterior wall facing, windowsills, countertops, coping and caps etc.

Clay products

Are made by shaping a plastic mass of clay and water which is then hardened by drying and firing. Glazed products require an initial firing to produce the ‘biscuit’ to which the glaze is then applied and the product re-fired in various sizes and shapes. All properties are affected by the composition of the raw material used.

 

Bricks         ̃They are produced as ‘common’ and ‘face bricks’ in a variety of sizes and shapes, but the prime factor controlling all brick dimensions is the size and weight of a unit that can be grasped in one hand. Four method of shaping are commonly used: 1 Hand moulding, 2 Extruding, 3 Dry pressing and 4 Machine moulding.
Bricks can satisfactorily resist compressive and low shear stresses, but they are not able to resist tensile stresses. The compressive stress of clay bricks varies from about 10 to 100 MPa, but the strength of brickwork is generally dependent on the quality of mortar used. Extruded bricks, even when heavily perforated, are stronger than solid pressed bricks.

 

Roof tiles   ̃ made in a variety of styles, including French tile, Spanish tile, Roman tile, English tile, Mission tile etc, but pattern used in Western Australia are mainly Marseille and Swiss.
Roof tiles are used for sloping roofs between about 15° and 50° inclination of rafter, and tile shape differ for each range of slope. It should be remembered that the rafter pitch is always steeper than the tile pitch.

 

Ceramics    ̃ all productions that results in baked clay of different grades of hardness and purity. The term ‘pottery’ is also used to categorise these products. Terms associated with ceramics are terra cotta, earthenware, stoneware, china and porcelain.

 

Ceramic tiles        ̃ available in many sizes and shapes. they are used as wall and floor tiles in bathrooms, washrooms, kitchens, laboratories etc.

 

Ceramic fittings   ̃or vitreous china for sanitary plumbing items such as toilet pans, wall and vanity basins, bath and showers etc.

Concrete products

Concrete is an artificial stone produced in a plastic condition by mixing together ‘aggregates’, (sand and crushed rock) and a ‘matrix’ (cement and water) all in controlled portions. The chemical reaction between the cement and water produces strong binding qualities so that on drying out the resulting material is hard, dense and able to resist compressive stresses. Climatic conditions also affect the quality of concrete. Steel bars incorporated in sections of the concrete giving it good tensile as well as compressive strength if correctly placed in the member

 

Concrete blocks                ̃ are available for brickwork in a great variety of shapes and sizes in hollow and solid              forms.

 

Special purpose blocks    ̃ can be made in a variety of shapes and patterns for decorative and ventilation purposes.

 

Paving blocks                   ̃ also now available in great variety. The interlocking system is well suited for vehicular              traffic

 

Roof tiles                           ̃ extruded concrete available in a wide range of profile and colour combination.

 

Kerbs and gutters           ̃ precast  concrete units for roads, industrial or domestic situations.

 

Steps and stairs             ̃ numerous pre-cast steps and stairs are available to simplify site work for these labour-           intensive items.

 

Tee beams                       ̃ often pre-stressed and available for various conditions from standardised forms.

 

Concrete pipes               ̃ made of spun reinforced concrete. These pipes are available in a wide range of sizes and          used extensively in civil engineering projects and large scale building work, especially          rainwater drainage, service ducts etc.

 

Utility blocks                  ̃ made for special purposes such as manholes, septic tanks, soakwells, landscaping etc.

 

Pre-cast items general   ̃ many other pre-cast items are available and more information about this can be obtain from           the Precast Manufacturing Association.

Lime silica bricks

Lime silica bricks      ̃ also called sand lime bricks, whitish in colour, smooth finished. Their characteristics vary                      considerably from clay bricks as they are much less durable than clay bricks. They should not                      be used in exposed locations. If used as internal leaf in combination with clay bricks some                      unusual cracking pattern in apartment-type buildings have been occurred, and more                      investigation of this phenomenon is needed.

Mortar

Mortar joints bond bricks together allowing the brickwork to act as a structural element to carry both vertical and lateral loads. The performance of brickwork depends very much on the properties of the hardened mortar, and the quality of the workmanship of the bricklayer. Mortar is a mixture of sand ,lime/cement and water, measured out by volume or weight, then thoroughly mixed together. The mortar should be mixed with a minimum amount of water that is possible to use and still maintain the proper plasticity. If mixed mortar loses water by evaporation and stiffened, additional water may be added and the mortar remixed. However, water should not be added to the mortar which has began to stiffen because the set has begun. Mortars should be used within two hours after mixing, under normal temperature condition. Mixing can be done in small mechanical cement mixers, or by hand.

 

There are three types of mortar used in brick and block work, 1 lime mortar, 2 cement mortar, and 3 composite mortar, each for a specific purposes.

 

Lime mortar           ̃ usually mixed in the proportion of one part lime to three parts sand by volume. The mortar has a low degree of shrinkage, is slowly hardening, and easy to work with.. It is much weaker in compression and shear than cement or composition (compo) mortars.

 

Cement mortar      ̃ mixed in different proportions, depending on the application. It is the strongest mortar, and is used where the brickwork is heavily loaded and where it is subject to damp, such as below the damp proof course (DPC) and in basement walls and in chimneys above the roof line. The mortar has a high degree of shrinkage, is quick hardening, and very hard to work with. Mortars which are rich in cement tend to cause unsightly cracking of masonry.

 

Composition mortar    ̃ also called cement/lime mortar, is an elastic term, covering a wide range of mixes. At one extreme is one part cement, three parts lime, and twelve parts sand (1:3:12), and at the other extreme three parts cement, one part lime, and twelve parts sand (3:1:12). Probably the most satisfactory mix for all-round general construction is one part cement, one part lime and six parts of sand (1:1:6).The presence of lime in such mixes gives good working qualities but reduces the rate of hardening and the final strength. Although the mix still shrinks on drying, the slower hardening rate tends towards less harmful type of cracking.


Masonry admixtures have many advantageous properties, retarding the setting time, repelling water, controlling efflorescence, increasing weather resistance, etc. but they have to be used correctly to work effectively. Admixtures are substances other than the prescribed materials of water, aggregate, and cementitious materials that are used to improve one or more of the recognized desirable properties of conventional masonry mortar.

Timber products

Timber is not only one of the oldest building materials, along with stone, earth and various vegetable materials, but has remained until today the most versatile and in terms of indoor comfort and health aspects, most acceptable material. Its a extremely complex material, available in a great variety of species and forms, suitable for all kinds of applications. The diversity of timber products and application requires a good knowledge of the respective properties and limitations as well as skill and experience in order to derive maximum benefits from timber usage.

 

Although only small portion of the timber harvested is used for building, the universal concern about the rapid depletion of forests, especially the excessive felling of large old trees (which take hundred of years to replace) and the great environmental, climatic and economic disasters that follow deforestation, has led to a great deal of research into alternative materials and rationalised timber utilisation. Since timber cannot be completely replaced by other materials, it shall remain one important building material. AS 1684 specifies the requirements timber framed construction

 

Structural (sawn)     ̃ raw sawn solid sections available in various stress-grades and dimensions for roof and wall framing. (usually green for hardwood and seasoned for softwood)

 

Glue-laminated         ̃ composed of layer of wood with the orientation of the grain of each layer usually in the same direction, or varied according to the intended use of the product. Straight or curved structural members of very large (even varying) cross-section and great length can be produced with low grade timber of small sizes, achieving high strength.

 

Plywood                    ̃ made of several plies (‘peeled’ off a pre-boiled log) glued together such that the direction of grain of each ply runs at right angles to the ply on either side, producing extremely large panels of greater strength than sawn timber boards.

 

Particle board            ̃ also known as chipboard, principally made of wood chips which are dried, blended with a synthetic resin and hot-pressed or extrusion-pressed to the desired shape. Hot-pressed boards are stronger than extruded boards.

 

Floor boards              ̃ are made with tongue-and-grooved edges from kiln dried timber. Parquet flooring consist of blocks of hardwood of various sizes which can be laid in a number of patterns such as herringbone, basket weave etc.

 

Joinery                       ̃ products made from seasoned and dressed timber to manufacture doors, window frames, window sills, cupboards, stairs and similar building elements

Metals

Ferrous metals
All ferrous metals are made from pig iron, which is produced by heating iron ore, coke, limestone and some other materials, in a blast furnace

 

Cast iron           ̃ alloy of iron, carbon (in excess of 1.7%), silicon, manganese and phosphorous. They have relatively low melting points, good fluidity and dimensional stability.

Wrought iron  ̃ is pure iron with only 0.02 to 0.03 % carbon content, is tough ductile and more resistant to steel, but expensive and unsuitable for welding.

Steel                 ̃ alloy of iron with carbon contents between 0.05 and 1.5 %, and with additions of manganese, silicon, chromium, nickel and other ingredients, depending on the required quality and use. Steel is subdivided in low carbon steel with less than 0.15% carbon, medium carbon steel with up to 0.5% carbon and high carbon steel with up to 1.5% carbon.

Alloy steel         ̃ steel with special classification; when the content of alloying elements exceeds certain limits or in which a definite range of alloying elements is specified.

 

Non-ferrous metals
Non-ferrous metals don't contain iron, for example aluminium, brass, copper (which can be remembered as ABC). You can also get non-ferrous metals as alloys eg, brass is an alloy of copper and zinc and bronze is composed of copper and tin

Aluminium            ̃ the third most commonly element, but difficult to recover as a metal (produced with very high                                      energy input and high cost.

Copper                  ̃ available in its pure form, or as alloy, such as brass, bronze, etc.

Lead                      ̃ used in its pure form, is the densest metal, but also the softest, and thus the weakest metal.

There are a few other metals, like zinc, tin, nickel, chromium, etc mainly used as constituents of alloys to suit a variety of requirements.

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Plaster, plaster products   

Plaster consist of lime, cement, mortar or gypsum plaster mortar, and is used as covering on walls and ceilings to provide a smooth continuous surface, hard enough to resist damage by impact upon its surface.

(wet-lining)            ̃ plaster is applied while plastic and dries out and hardens after application. Some surface preparation may be needed before plastering. Most rendering is done in two-coats, a float in cement mortar and a finish coat with hydrated lime or plaster of Paris.

 

                                A cement mortar is used for plastering the exterior of buildings to give extra protection against the penetration of moisture and to provide a desired texture.

 

Plasterboards

(dry-lining)            ̃A rigid fire-resistant board made of different sizes and thickness for both sheathing and finishing of interior walls and ceilings.

Gyprock                 ̃ plasterboard made of a core of gypsum plaster set between and bonded to outer coverings of heavy cardboard.

Plasterglass           ̃ mixture of gypsum reinforced with strong durable fibreglass. The interwoven fibreglass strandsprovide the extra strength and resilience against cracking

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Glass

The art of glass making is very old, and today the industry uses basically the same raw materials as did the ancient glassmakers. However, the methods of manufacturing have changed and extremely improved resulting in high production rates, superior glass, and very great sheet sizes. Glass is a hard, brittle non-structural building material produced by the fusion of a mixture of silica with soda, lime and other minor ingredients such as magnesia and alumina, to produce a material for general window glazing.

Float glass                  ̃ transparent with 85% light transmission and a truly flat glass with undistorted vision. It is formed by floating a continuous ribbon of molten glass over a bath of molten tin at a controlled rate and temperature.

 

Rolled glass                ̃ produced by passing the ribbon of glass between rollers during cooling. The roller regulate the thickness and impart the pattern to the glass. It can be reinforced with wire mesh for safety and fire resistant glazing purposes.

 

Insulating glass         ̃ consist of two or more panes of glass, separated by an air space, and joint at the edges to produce a hermetically sealed unit. The air space (usually 13 mm) is dehydrated with a drying agent to ensure no moisture build-up.

 

Toughened glass      ̃ plate glass which is subjected to a process of heating and sudden cooling results in a toughened glass with increased mechanical strength and greater resistant to impact and temperature changes. Also referred to as safety glass. It disintegrates into small pieces and powder when broken.

 

Tinted glass               ̃ this type of glass is specially tinted to reduce solar heat and cut down glare.

 

Laminated glass   ̃ also referred to as safety glass, made from two or more layers of glass bonded together with a film of a tough transparent plastic. The main reason for laminating glass in this manner is to increase its resistant to breakage. It, like toughened glass, is used in vehicles and aeroplanes rather than in building.

 

Their are variety of other types available such as:

Lead glass             ̃ lead oxide is added to the glass to accomplish protection from dangerous rays such as X-rays and gamma rays.

Mirrors                   ̃ are made by a continuous silvering process on large sheets of glass. The glass is cleaned, tinned, silvered, then coppered, painted and baked to protect the silver coating.

Glass blocks          ̃ they are made in two separate halves which are heat-sealed together to form a hollow unit with reasonably high thermal efficiency and sound insulation.

Glass tiles              ̃ another glass product. Its primary purpose is to admit light into the building.

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Plastics

The term ‘plastics’ refers to a group of organic materials, most of which are synthetic and which are shaped or formed by the application of heat and pressure. Some plastics can be softened by heating, whereas other are unaffected  unless they are heated to a sufficient high temperature to cause decomposition. All plastics fall into two general classifications:

1) thermoplastics and (2)thermosetting plastics, called thermosets.

 

The properties of may plastics make them desirable materials for use over a wide area of the construction field. Properties such as transparency, resistance to discolouration, weatherproof, good dimensional stability, toughness, high impact resistance, low moisture absorption, ductility, good adhesive qualities, resistance to chemicals, etc. With the perfection of manufacturing process, any size and shape can be produced quickly and accurately. Plastics are now being used as structural and non-structural components, in composite applications, and as auxiliary material.

 

Thermoplastics       ̃ become soft when heated and hard when cooled, regardless of the number of times the process is repeated. This is possible because thermoplastics have linear molecule chains, which move in relation to one another when heated or cooled and solidify into new shapes without any significant chain breakage occurring.

            Examples:   ̃ Polythene, Polypropylene, Polyvinylchloride (PVC), Polystyrene Nylon Acrylics, eg Perspex etc.

 

Thermosets             ̃ do not re-soften or melt on further application of heat and retain their shape because of the formation of cross links between molecule in adjacent chains. The result is a complex, interconnected network, in which the chains are no longer free to move, making the structure more rigid but also more brittle.

              Examples:   ̃ Epoxy resin, Polyester resin, Synthetic rubbers, Polyurethanes Phenolics, eg Bakelite, Urea and melamine formaldehyde resins

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Coatings

The most common form of coating is paint. The base or content can vary considerably. The choice of coating used depends upon the application, examples of which are follows:

Metallic                  ̃ electroplating, hot dipping, metal spraying, condensation of metal vapours, metal cladding cementation.

Non-metallic          ̃ oxides, phosphates, chromates.

Paints                     ̃ metal-rich, oil-based, plastic-based, resin-based, rubber-based.

 

Coatings of paint are applied to nearly every type of article and structure. These coatings provide protection against corrosion, increase the resistance to hard wear, and give the item or structure a more pleasing appearance.

A paint consists of a suspension of fine pigments in a liquid medium, sometimes called vehicle, and is applied in a liquid or plastic condition and subsequently hardens to form a solid coating. The solid particles in a paint are called pigments. The pigment is chosen because it possesses certain properties or a particular combination of properties, (eg anti-corrosive properties). It may be used because it confers some or all of the following properties on the paint film: colour, greater strength and adhesion, improved durability and weathering properties, reduced gloss, modified flow an application properties, etc.

Pigments are either:   ̃ synthetic, (ie man made),or

                                      ̃ natural and organic or inorganic chemicals.

The desirable properties of the medium or vehicle are:

                                      ̃ it thoroughly wets the particles of the pigment,

                                      ̃ it should be sufficient viscous to hold the particles in suspension when the paint is drying, but sufficiently fluid to make application easy.

The performance of any coating material is related directly to the thoroughness and quality of the preparation of the surface prior to application of the coating.

 

Priming paints          ̃ these are the first coat paints used to seal the surface, protect the surface against damp air, act as a barrier to prevent any chemical action between the surface and finishing coat, and to give a smooth surface for the subsequent coats. Priming paints are produced for application to wood, metal and plastered surfaces.

 

Undercoating paints   ̃ these are used to build up the protective coating and to provide the correct surface for the finishing coat(s). Undercoat paints contain a greater percentage of pigment than finishing paints and as a result have matt or flat finish. To obtain a good finish colour it is essential to use an undercoat of the type and colour recommended by the manufacturer.

 

Finishing paint         ̃ a wide range of colour and finishes including matt, semi-matt, eggshell, satin, gloss and enamel are available. These paints usually contain a synthetic resin which enables them to be easily applied, quick drying and have good adhesive properties.

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Adhesives

The art of making and using glues of various kinds has been known for a very long time. Many of the materials used in ancient times were natural products, such as bitumen and tree resins, while others were made by hand by processes which were kept closely guarded secrets. Adhesiveness is the ability of a material to fix itself and cling to an entirely different material.

 

The growth of the plastic industry has resulted in the development of many new glues made from synthetic resins.

 

Animal glue            ̃ is available in either solid or liquid form.  Animal glue has excellent bonding properties with                  wood, leather, paper or cloth, developing up to 90 MPa in shear.

 

Casein glue             ̃ made from protein materials, is a dry powder to be mixed with water. It has good bonding power for wood-to-wood or paper-to-wood application, and will develop the full strength of the wood in most situations.

 

Asphalt cements    ̃are thermoplastic materials made from asphalt emulsion or asphalt cutbacks. They have good bond to paper and concrete and are used mainly for roofing applications.

 

Urea formaldehyde resins  ̃are available in powder form, to be mixed with water, and in liquid form, which requires the addition of a hardener. They are thermosetting in nature with excellent bond to wood, leather, or paper, having a shear strength up to 21.5 MPa

 

Phenolic resin glues  ̃ made in both dry and liquid form. They are thermosetting glues as the above with similar shear strength and excellent bond to wood and paper.

 

Melamine resins          ̃ also thermosetting glue manufactured as a powder with a separate catalyst. They have excellent bond with wood or paper.

 

Epoxy resin adhesives   ̃ are among the most versatile of all modern adhesives, since formulation of the material may be developed to suit a particular requirement. They are thermosetting , manufactured in liquid form with a separate catalyst. The amount of catalyst added to the resin determines to a large extent the type of curing required. They have excellent bond with wood, metal, glass, and masonry.

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Sealants

A sealant is a material used to fill the joint between two adjoining elements of structure in order to render it moisture and air-tight. Often the successful performance of other building components depends on the proper functioning of the joints between them. The width of the joint to be used in any specific case depends on the calculated amount of movement at the joint and the type of sealant to be used. To be useful in such variety of functions, a sealant must have a number of specific properties:

·         It must be able to adhere to surfaces with which it comes in contact.

·         It must remain workable over a considerable range of temperature.

·        It must be able to form a tough, elastic skin over the surface, while the interior of the mass remains flexible.

·        It must be able to stretch or elongate with changes that may occur in the width of the joint

·         It must be able to recover well after having been extended or compressed.

It must have very low sensitivity to water

 

Mastics   ̃ can be oil based general purpose mastic, which is a low cost general purpose caulking compound for most common building materials, or a rubber/bitumen sealing compound, for sealing joints where bituminous compounds are accepted (eg retaining walls, roofing, flashings). Accommodates up to ±7½% movement.

 

Silicone    ̃ mostly used as one part sealant, which accommodates up to ±25% movement. There are made for a variety of different applications such as for all types of glazing, joints in wall tiling, sealing high movement joints in external wall cladding, etc

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