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Acm Unit v

Advance Construction Materials

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Acm Unit v

  1. 1. ADVANCED CONSTRUCTION AND MATERIALS Niha Najaf (13131AA035) Mona Ilyas (13131AA031) Muznah Mirza (13131AA032) Madeeha Nishat (13131AA017) Sameera Tanveer (13131AA044) Rushdiya Fathima (13131AA043)
  3. 3. PLASTIC ◦ Plastics are used on a daily basis throughout the world. ◦ The word plastic is a common term that is used for many materials of a synthetic or semi-synthetic nature. ◦ The term was derived from the Greek plastikos, which means “fit for molding.” ◦ One way plastics changed the world was in cost. It was so much cheaper to manufacture than other materials and the various ways it could be used was staggering ◦ plastics are used in an enormous and expanding range of products, from paper clips to spaceships. ◦ They have already displaced many traditional materials
  4. 4. ADVANTAGES ◦ Light in weight. ◦ Can be easily molded and have excellent finishing. ◦ Possess very good strength and toughness. ◦ Corrosion resistant. ◦ Good thermal and electrical insulating property. ◦ Good water resistant and possess good adhesiveness. ◦ Strong and cheap to produce. ◦ Unbreakable. ◦ Wide choice of appearance, colors and transparencies ◦ Plastic is a nonrenewable resources ◦ Low heat resistant and poor ductility. ◦ Combustibility - Many plastics are flammable unless treated. ◦ Low modulus of elasticity: makes them unsuitable for load-bearing applications. ◦ Produces toxic fumes when it is burnt ◦ It is a recycle process, but it is very costly. ◦ Aging effect, hardens and become brittle over time DISADVANTAGES PLASTIC - AS A BUILDING MATERIAL
  5. 5. TYPES OF PLASTIC THERMOPLASTICS ◦ Chemical structure remains unchanged during heating and shaping ◦ More important commercially, comprising more than 70% of total plastic tonnage High Density Polythene Low Density Polythene Poly Vinyl Chloride (PVC) Polypropylene Polystyrene Acrylo-nitrile (Nylon) ABS Melamine Formaldehyde ABS Poly Vinyl Acetate (PVA) Acrylic (Perspex) Elastromers THERMOSETTING ◦ Undergo a curing process during heating and shaping, causing a permanent change (cross-linking) in molecular structure. ◦ Once cured they cant not be remelted. Epoxy Resin Polyester Resin Glass Reinforced Plastic Carbon Fibre Plastic Melamine Formaldehyde
  6. 6. THERMOPLASTICS ◦ High Density Polythene: HDPE is used for Buckets, Basins, Bottles, Containers and is extensively used in both Blow molding & Injection molding process. ◦ Low Density Polythene: Most LDPE application is film based. Industry uses also include wire & cables coating, injection & Blow molding is used for plastic bags and bottles. Properties: Soft, Flexible, Good Electrical insulator ◦ Polyvinyl Chloride: PVC is used for Gutters, Drain Pipes, Window/Door Frames & Shutters, Plumbing Fixtures, Furniture equipment, etc…It is often used in the Extrusion Process (larger length possible). Properties: Rigid, Water & Weather Resistant, Light Weight , Ease of fabrication & Installation. ◦ Polystyrene: It is used extensively in the Packaging Industry. It is also widely used in Insulate Buildings, in Refrigerators, etc. Properties: Soft, Lightweight, Good Insulator, Water resistance. ◦ Acrylic: Acrylic is used for Bath’s Fixtures & Sanitary wares, Lighting, Display Stands. Properties: Stiff, Hard, Brittle , Scratches easily. It is generally used as a waterproof.
  7. 7. THERMOSETTING ◦ Epoxy Resin: Adhesive of as a liquid for casting. Properties: Strong (When Reinforced), Clear ◦ Melamine Formaldehyde: It is commonly known as Formica is a composite material made from resin and layers of paper, commonly used for worktops. Properties: Clarity, Stability to Heat, Light, Chemicals, Abrasion and Fire. ◦ Glass Reinforced Plastic: It is a composite material made from Resin and Glass Fiber Sheet. This combination produces a lightweight yet extremely strong material and used everywhere from Speed boat hulls to Aircrafts, Roofing sheets, etc. Properties: Very Strong, Lightweight, Easily workable.
  8. 8. THE BUILDING INDUSTRY ◦ PIPES : Electrical Conduits, Rain Water & Sewage pipes, Plumbing, Gas Distributions. ◦ CABLES : PVC Insulation on cables, Insulation Tapes . ◦ FLOORINGS : Flooring tiles & Rolls . ◦ DOMES / SKY LIGHTS : Opaque as well as transparent. ◦ ROOFING : Colored or Double skinned for insulation. ◦ WINDOWS & DOORS : Extruded sections for Door and windows and panels. ◦ STORAGE TANKS : Storage tanks. ◦ HARDWARE ACCESSORIES : Washers, Nut bolts, Sleeves, Anchoring wires. ◦ TEMPORARY STRUCTURES: Guard cabins, tents ◦ INSULATION MATERIALS: PVC sheets, insulating membranes.
  9. 9. PLASTIC FLOORING ◦ Available in two types: ◦ Hard polypropylene ◦ Soft PVC. ◦ Each type of plastic flooring is incredibly durable. ◦ Generally used for Garages, and Warehouses ◦ Both types are capable of supporting extreme weight loads and resistant to oils/solvents. ◦ PVC is a softer, more pliable option which typically provides a softer flooring for standing or working. ◦ PVC flooring is less prone to wear and tear. It also decreases the sound pollution level and can be cleaned easily. PLASTIC FLOORING LIKE WOOD FINISH
  10. 10. PLASTIC WALLS REASON  Durable  Waterproof  Easy to clean  Hygienic Wall & Ceilings  Cost Effective  Easy to Install  Choice of colors & styles A structural insulated panel (SIP) is a sandwich of expanded polystyrene amidst two slim layers of oriented strand board. This type of pre-fab, composite wall board can be transferred to the work place easily for a particular task and provide good support to columns and other associated essentials during renovation. APPLICATIONS FOR PLASTIC WALLS  Commercial kitchens  Bathrooms  Washrooms  Canteen Walls and Ceilings  Food Processing Areas  Changing Areas  Fast Food Outlets  Food Storage
  11. 11. PLASTIC ROOFING ◦ UPVC products are now frequently used in place of the more traditional products for external cladding panels, soft boards, particularly on new buildings. ◦ Polycarbonate panels have a high impact strength and have been known to withstand hurricane force winds when applied to outdoor displays or building structures such as skylights or archways. ◦ The lightweight panels minimize the structural support needed by the building and its transparency allows for more natural light and when using thicker guages can provide greater insulation value. CLADDING PANELS • Corrugated plastic sheeting has been used for roofing in conservatories and buildings where transparent panels have been required. • To protect the outer surface of the roof from damage, two layers of different plastic materials are required. The upper part is made of colored thermoplastic olefin or vinyl while the lower part consists of polyurethane foam which consumes less energy and keeps the interior of a house cooler.
  12. 12. SOUND & THERMAL INSULATION ◦ Sound insulation can be provided by either a simple and heavy or a light and complex construction , which is now replaced by the rubber and plastics materials. ◦ Apart from sound insulation, buildings need thermal insulation also. This can be met by using light weight aerated concrete building blocks during the construction of the building or by incorporating foamed plastic sheeting within the structure. ◦ Typical foamed plastics include rigid polyurethane foam and expanded polystyrene, although various other foamed plastics may also be used. ◦ Plasterboard can be readily obtained with a 25 mm foamed polystyrene backing. Other composite sheet building products can be obtained with polyurethane foam cores. They can be kept clean with very little effort ◦ Polyurethane spray is frequently used for insulation when constructing green or low energy buildings. Rigid polyurethane foam is known for its high thermal resistance which promotes temperature consistency. Polyurethane foam is also popular because it is lightweight, chemical resistant, and flame retardant. Due to its closed cell nature, polyurethane insulation performs as an air barrier, resulting in significant energy savings
  13. 13. PLASTIC DECORATIVE ELEMENTS ◦ The normal structure of a plastic decorative laminate includes a sheet of decorative paper impregnated (saturated) with one or more resins. ◦ Plastic decorative laminates have a wide range of uses, they can be used in the furniture industry for kitchen cabinet counters, bookshelves and door linings, among many other things. In the building industry they can be used for partitions screens in order to divide space in offices, houses, etc... PLASTIC ADHESIVE AND SEALANTS • There are also water-based versions that can provide better heat resistance. • Generally solvent-based, these cost effective, gap-filling adhesives are suitable for bonding sheet flooring, adhering skirting's and architraves, signs and wall panels. • They have good adhesion to most substrates (especially porous materials such as wood, concrete, brick and plasterboard). • Sealants- create a flexible, durable bond which is vibration- and shock resistant.
  14. 14. The Monsanto House of the Future was constructed at Disneyland in 1957. The frame and structure of the house were 100% plastic. The house had four cantilevered wings floating above beautifully landscaped grounds and waterfalls. Water Cube; The National Aquatic Centre in Beijing China
  15. 15. WHY USE PVC IN BUILDING? DISADVANTAGESADVANTAGES • Durable • Cheap material • Easily available • Ease of installation, easy to clean • Can be casted to any shape. • Easily recyclable • Wide range of colours and patterns • Water proof • Flexibility • Good electric shock proof • Fire resistant(wide temperature) • Its production causes pollution. • They cannot be used at high temperatures. • They do not have the same strength as cast-iron or galvanized irons pipes. • Higher density than many plastics. POLY VINYL CHORIDE
  16. 16. Strong and lightweight PVC's abrasion resistance, light weight, good mechanical strength and toughness are key technical advantages for its use in building and construction applications. Easy to install PVC can be cut, shaped, welded and joined easily in a variety of styles. Its light weight reduces manual handling difficulties. Durable PVC is resistant to weathering, chemical rotting, corrosion, shock and abrasion. It is therefore the preferred choice for many different long-life and outdoor products. BENEFITS OF PVC OVER OTHER MATERIALS
  17. 17. Cost-effective PVC has been a popular material for construction applications for decades due to its physical and technical properties which provide excellent cost-performance advantages. Safe material PVC is non-toxic. It is a safe material and a socially valuable resource that has been used for more than half a century. It is also the world’s most researched and thoroughly tested plastic. Fire resistant PVC products will burn when exposed to a fire. PVC products however are self- extinguishing, i.e. if the ignition source is withdrawn they will stop burning. Because of its high chlorine content PVC products have fire safety characteristics, which are quite favorable as they are difficult to ignite, heat production is comparatively low and they tend to char rather than generate flaming droplets.
  18. 18. Good insulator PVC does not conduct electricity and is therefore an excellent material to use for electrical applications such as insulation sheathing for cables. Versatile The physical properties of PVC allow designers a high degree of freedom when designing new products and developing solutions where PVC acts as a replacement or refurbishment material. Vinyl Cladding PVC wall and ceiling claddings and weatherboards are designed as long life products requiring no painting and little maintenance. Interior and exterior cladding is available with coloured, textured and moulded surfaces. PVC's durability, high thermal insulation and excellent weathering performance APPLICATIONS OF PVC
  19. 19. Vinyl roofing membranes  Pitched or flat, clear or coloured, PVC roofing membranes suit homes, commercial buildings, sports facilities, factories and lightweight structures  The 80% solar reflectivity of PVC will reduce a building’s air conditioning demand and may reduce 'heat island effects' in the urban environment. A light weight addition to a building.  A good quality PVC membrane can be highly effective in preventing water and root penetration, so they are now often specified in 'green' or living roof systems. Vinyl floor coverings  PVC is the main polymer used for sheet and tile flooring.PVC resilient flooring is widely used in hospitals, schools, sporting clubs and commercial kitchens where slip resistance and high levels of safety and hygiene are required.  Vinyl floors are low maintenance, hygienic and fire resistant. Sheets are joined together by heat welding which prevents water or moisture from seeping through gaps and therefore are ideal for wet floor areas such as in healthcare facilities.
  20. 20. Window and Door Profiles  PVC windows are proven performers in reducing energy consumption for heating and cooling and consequently, over their whole life cycle, can reduce greenhouse gas emissions by as much as 48-61% compared with aluminium framed windows  The tight seals of PVC window and door profiles and the ease with which they can be fabricated for double and triple glazing make PVC an excellent choice in energy efficient buildings. Fencing, Decking and Railing  PVC is used for many outdoor applications as a timber replacement including decorative and functional fencing, railings and decking.
  21. 21. TYPES OF PVC UPVC (UNPLASTICIZED POLYVINYL CHLORIDE) • Unplasticized Polyvinyl Chloride Pipes (UPVC) can be used in a wide range of applications including electrical and telephone cables, sewer pipes and potable water supply. • It has an advantage over PVC in that it offers less resistance to flow than conventional pipes resulting in minimal flow loss. • Commonly use for doors and windows frames . CPVC (CHLORINATED POLYVINYL CHLORIDE) • CPVC stands for Chlorinated Polyvinyl Chloride (that extra chlorination makes all the difference), and is distinctive for its yellowish colour. • This plastic pipe is somewhat flexible and has thinner walls than standard PVC, though is more resistant to heat, and works well for hot water supply applications. • CPVC also has an advantage over PVC in colder climates in that it acts as an insulator, thus preventing cold water pipes from forming condensation when water temps get very low.
  22. 22. ROOFING ◦ Reinforced pvc roofing is easy to install, ◦ Pvc has low maintenance requirements and lasts for over 30 years. • Durable • Freedom of aesthetic effects – available in a wide range of colours and patterns • Ease of installation, easy to clean • Easily recyclable • Variable thickness FLOORING
  23. 23. ADVANTAGES OF VINYL WINDOW ◦ Lower energy costs. Vinyl windows keep heat in during winter and out during summer. This reduces heating and air conditioning usage for lower energy bills. ◦ Maintenance free. Vinyl windows are nearly 100 percent scratch free. They never have to be painted, scraped, or stained and they’re easily cleaned with soap and water. Because they’re resistant to the elements, they don’t age as fast as other windows. ◦ Inexpensive. Vinyl is the least expensive of all window materials, but this doesn’t mean vinyl windows are low quality. Vinyl is durable, and it won’t rust or corrode. ◦ Variety. Vinyl windows have many colour, size, and style options. They can also be custom made. Colours range from champagne to forest green, and sizes range widely. Vinyl windows are available in styles from awning to picture. • Vulnerability. In extreme weather conditions vinyl can discolour. This is especially true in intense heat. They can’t be repainted, so when this happens, the window has to be replaced. • Customization costs. Vinyl windows are difficult to shape, so manufacturers use a process called extrusion to get the job done. For standard windows the costs are minimal, but custom windows can cost more depending on the scale of the project. • Low resale value. Vinyl windows don’t add as much value to the home as do other types of window replacements. DISADVANTAGES OF VINYL WINDOW
  24. 24. PVC Wall Construction Systems  Concrete-filled PVC stay-in-place (SIP) formwork wall construction systems is being used to offer significant benefits in terms of construction timeframes, life cycle costs and embodied energy performance.  These new systems can be used to replace load-bearing conventional precast concrete, tilt-up or masonry block walls and are today used for basements, stair and lift shafts, blade columns, irrigation tanks, retaining walls and other areas, and in buildings 30 storeys high.  Traditional, temporary formwork using timber, plywood or steel is labour intensive. Glass-reinforced plastic, fibre- reinforced plastic, thermoplastics (PVC, polystyrene), fibre cement and metals are examples of materials used to pre- fabricate formwork for permanent systems where the materials remain in place for the life of the building. The components can be interconnected to create formwork that can be erected with a high level of efficiency.  Concrete is generally used in construction for its high compression strength, its drawbacks include the need for reinforcement to compensate for its poor tensile strength. Using SIP formwork helps overcome these problems as the concrete is sealed or protected from the environment by the formwork for the life of the building. The connectors in the latest SIP formwork systems facilitate concrete flow and consolidation and there’s usually no need to vibrate the concrete
  25. 25. TEE (SOC) ◦ Use – tee joint in three sides for joint with pipe and all side shave the same size. REDUCER TEE (SOC) ◦ Use – reducer tee in one side 15mm so another two side 20mm that’s called reducer tee. FBT TEE • Use – one side • joint with tap. ELBOW 45 (SOC) • Use – 90 degree turn used for small turn. BRASS ELBOW • Use – one side of brass. ELBOW 90 (THREAD) • Use – one side of thread and 90 degree turn. ELBOW 45 (SOC) • Use – 45 degree turn. CROSS(SOC) • Use – cross joint four side joint available. COUPLER(SOC) • Use – joint two pipes two side available. REDUCER COUPLING(SOC) • Use – one side 25mm so another 15. Use for high to law water supply thus called reducer . PLUMBING
  26. 26. BALL VALVE ◦ Use – up side joint with valve for close water supply. END CAP (SOC) ◦ Use – to end the line. UNION • Use – joint two lines. REDUCER BUSHING • Use - joint two lines in tight fitting both sides have a thread. FAPT (PVC THREAD) • Use – joint two lines in tight fitting both sides have a thread. PVC STRAP • Use – pipe joint with the wall. TANK ADAPTER • Use- one side joint with tank and another side available reducer. LONG RADIUS BEND • Use - long turn pipe joint. FABT (BRASS THREAD - FEMALE) • Use – joint two lines in tight fitting both sides have a thread. MAPT (BRASS THREAD - FEMALE) • Use- one side joint with fabt brass thread and another with pipe.
  28. 28. FIRE RESISTANT MATERIALS : GYPSUM : ◦ Gypsum board is an excellent fire-resistive building material. ◦ Its non combustible core contains nearly 21% chemically combined water, as described earlier, which, under high heat, is slowly released as steam. ◦ Because steam will not exceed 100 degrees Celsius under normal atmospheric pressure, it very effectively retards the transfer of heat and the spread of fire. ◦ Even after complete calcination, when all the water has been released from its core, gypsum board continues to serve as a heat-insulating barrier. ◦ Moreover, tests conducted show that gypsum board has a low flame-spread index and a low smoke-density index. ◦ When installed in combination with other materials in laboratory-tested wall and ceiling assemblies, gypsum board serves to effectively protect building elements from fire for
  29. 29. GYPSUM : DURABILITY : ◦ Gypsum board is used to construct strong, high quality walls and ceilings that offer excellent dimensional stability and durability. ◦ Surfaces created using gypsum board are easily decorated and refinished ECONOMY: •Gypsum board is readily available and easy to apply. •It is an inexpensive wall surfacing material that provides a fire resistant interior finish. •Gypsum board building systems can generally be installed at significantly lower labor costs than most alternate systems. Versatility: •Gypsum board satisfies a wide range of architectural requirements for design. Versatility Gypsum board satisfies a wide range Of Architectural design requirements. Ease of application and repair, high performance, widespread availability, and decorative adaptability combine to make gypsum board an unmatched surfacing product.
  30. 30. ◦ TYPES AND APPLICATION 1/4-in. A low cost gypsum board used as a base in a multi-layer application for improving sound control, or to cover existing walls and ceilings in remodeling. 5/16-in. A gypsum board used in manufactured housing. 3/8-in. A gypsum board principally applied in a double-layer system over wood framing and as a face layer in repair or remodeling. •1/2-in. Generally used as a single-layer wall and ceiling material in residential work and in double-layer systems for greater sound and fire ratings. •5/8-in. Used in quality single-layer and double- layer wall systems. The greater thickness provides additional fire resistance, higher rigidity, and better impact resistance. •3/4-in. Used in a similar manner to 5/8-in. •1-in. Used in interior partitions, shaft walls, stairwells, area separation walls and corridor ceilings.
  31. 31. CONCRETE Concrete, one of the most common building materials, is also an excellent fire- resistant material. It is non-combustible and has low thermal conductivity, meaning that it takes a long time for fire to affect its structural, load-bearing ability, and it protects from the spread of fire. It's actually significantly more fire-resistant than steel, and often used to reinforce and protect steel from fire. However, it's important to note that not all concrete is created equal. It consists of cement and aggregate, and the particular kinds of aggregate materials used can vary, as well as the amount used. Aggregate can make up 60 to 80 percent of the concrete's volume. The exact fire-resistance properties change depending on the type and amount of aggregate used. Natural aggregates tend not to perform as well. Moisture in the aggregate can expand when heated, causing concrete to sinter after long exposure. Concrete is often listed as among the best fire-resistant roofing materials, too. And you shouldn't overlook the roof as essential in fire-protection, since it's extremely vulnerable to sparks blown from wild land fire.
  32. 32. STUCCO Stucco is a plaster that has been used for centuries for both artistic and structural purposes. Modern stucco is made of Portland cement, sand and lime, and it serves as an excellent and durable fire-resistant finish material for buildings. It can cover any structural material, such as brick or wood. It usually consists of two or three coats over metal reinforcing mesh. A one-inch (2.54-centimeter) layer of stucco can easily lend a 1-hour fire rating to a wall. Roof eaves (overhangs) are a fire hazard, but they can be protected with an encasement of fire-resistant material. Stucco is often recommended as one of the best materials for boxing in hazardous eaves. Stop Fire and Stay Stylish Because of the versatility in finishing techniques, stucco can come in various colours and textures. This means that it's easily adaptable to various architectural styles, including Prairie School, Mediterranean, Tudor and South-western. This way, you don't have to sacrifice beauty for practical fire-resistant protection.
  33. 33. BRICKS : ◦ As bricks are made in a fire kiln, they're already highly resistant to fire. However, it's true that individual bricks are much more fire-resistant than a brick wall. ◦ A brick wall is held together with mortar, which is less effective. Nevertheless, brick is commonly cited as among the best building materials for fire protection. Depending on the construction and thickness of the wall, a brick wall can achieve a 1-hour to 4-hour fire-resistance rating. ◦ So, although some materials are more fire-resistant than others, several factors might influence a builder's decision, including cost effectiveness, ease of installation and climate. Brick Still Isn't Perfect ◦ Unfortunately, brick can be expensive and heavy compared to other building materials. It's also not very effective at insulation, hence requiring supportive insulating materials to make a building energy-efficient.
  35. 35. SYNTHETIC BOARDS Guide to Synthetic Boards for Deck Construction : SYNTHETIC & COMPOSITE DECK BOARDS : Synthetic deck board choices for deck floors & Porches SYNTHETIC DECKING FOR DECK & PORCH FLOORS ◦ Manufacturers have introduced a wide range of synthetic decking products, most of which promise wood like appearance and low or no maintenance. ◦ Most fall into a few categories discussed below, but each has unique characteristics and installation requirements. In all cases, review the product specifications and, if possible, look at an installation before purchasing
  36. 36. SYNTHETIC BOARDS : ◦ In general, composite decking materials are dimensionally stable, impervious to the elements, and can be worked more or less like wood. The solid products are installed like wood decking. Special screws designed for composite decking leave a clean hole without dimpling around the screw head. ◦ Although these deck surfaces are largely impervious to the elements and contain no food source for mold or mildew, manufacturers do point out that a dirty deck can support mold and mildew growth and recommend periodic cleaning with a deck cleaner to prevent this. ◦ Also synthetic decking is vulnerable to oil and grease stains, which can be difficult to remove if not cleaned right away with a degreasing agent.
  38. 38. ACOUSTIC MATERIALS are things that have ability to absorb redundant noise and enhance transmission of sound. They play an important role in determining the quality of your auditory experience in a number of settings like offices, restaurants, concert halls, schools, auditoriums, healthcare facilities and gymnasiums. • SOUND ABSORBERS • SOUND DIFFUSERS • NOISE BARRIERS • SOUND REFLECTORS • These sound absorbing acoustical panels and soundproofing materials are used to eliminate sound reflections to improve speech intelligibility, reduce standing waves and prevent comb filtering. • Typical materials are open cell polyurethane foam, cellular melamine, fiberglass, fluffy fabrics and other porous materials. A wide variety of materials can be applied to walls and ceilings depending on your application and environment. • These materials vary in thickness and in shape to achieve different absorption ratings depending on the specific sound requirements. WHAT ARE THE ACOUSTIC MATERIAL? TYPES OF ACOUSTIC MATERIALS: SOUND ABSORBERS
  39. 39. SOUND ABSORBERS: ACOUSTICAL FOAM PANELS • These acoustical foam sound absorbers are used in a wide variety of applications ranging from Recording and Broadcast Studios to Commercial and Industrial Facilities. Available in Polyurethane or in a Class 1 Fire Rated foam. These products can be applied directly to walls, hung as baffles or used as freestanding absorbers. Design enables you to increase thickness quickly by nesting layers. Standard patterns include wedge, pyramid, max wedge for low frequency absorption, ceiling baffles, bermuda triangle traps for corners, sounds cylinders free standing absorbers Anechoic wedges are ideal for controlling low frequency sound to create a room that is perceptually devoid of sound. Absorbers are lightweight open cell foams used when a Class 1 fire rated foam is required. Standard patterns include Wedge, Pyramid, Max Wedge, Ceiling Baffles and more. These can easily mount to walls or ceilings FIRE RATED FOAM ANECHOIC WEDGES STANDARD POLYURETHANE FOAM PATTERNS
  40. 40. ◦ WHITE PAINTABLE PANELS: • It is a white acoustical wall panel with a soft textured appearance. The two foot by one foot dimension provides installers flexibility to mount acoustical panels around existing objects. In addition to reducing echo and reverberation, these acoustical panels are used to create unique designs and patterns. The glass fiber core is faced with a paintable covering. This allows you to match or complement existing wall colors by applying a light coat of flat or matte spray paint. To customize the look even further, many local printing companies now have the capability to produce an image directly to the face of these panels. ∞ Quick & Easy acoustical solution ∞ Soft drywall texture appearance ∞ Create unique patterns ∞ Panel size allows for flexible mounting options ∞ Paintable & Printable finish CONSTRUCTION: " Fiberglass 6 PCF acoustical core + molded fiberboard + paintable facing. Resin hardened square edges . Paintable finish covers face and exposed edges. Class A rating per ASTM E 84 Panel Size: 2' x 1' (24 inches by 12 inches) Thickness: 1-1/8" Quantity per box: 10 panels. SUSTAINABILITY: This product bears the Green Cross label for recycled content. The acoustical substrate is certified on average to contain at least 35% recycled glass, with 9% post-consumer and 26% pre-consumer content. MOUNTING: Installs using standard impaling clip method. (adhesive by others) Other mounting options shown below. MOUNT IN CORNERS USING CORNER CLIPS. MOUNT ON TWO INCH STAND OFF CLIPS
  41. 41. ◦ FABRIC WRAPPED PANELS Acoustical sound panels utilize 6-7 PCF glass fiber material for maximum absorption. Available as wall panels, ceiling tiles, hanging baffles, acoustical clouds and bass traps, with more than 50 standard colors to choose from, these materials will look as good as they sound. The standard sizes and configurations best maximize raw materials, however, many of these products can be customized to meet specific requirements should you need material sized to fit or other finishes or coverings. WALL PANELS: Used to reduce echo and reverberation in applications, small and large. These panels are manufactured from a rigid high density (6-7 PCF) glass fiber acoustical board and covered with an acoustically transparent fabric. CEILING CLOUDS Ceiling clouds reduce reflected sound in areas such as theaters, restaurants, arenas, shopping malls, convention centers, recording and broadcast rooms, or anywhere absorption is required. CEILING TILES • Ceiling Tiles are an excellent choice for many ceiling grid applications requiring high absorption. CEILING BAFFLES •All surface faces and edges of the glass fiber core are wrapped in fabric to match or accentuate room décor . Ceiling Baffles absorb sound on all sides and edges. BROADBAND ABSORBER •Sculptured sound absorbing modular units used for walls, as corner traps, bass traps and ceiling applications. Available in half-rounds or quarter-rounds.
  42. 42. Noise Barriers & Vibration Control: These materials range from dense materials to block the transmission of airborne sound to devices and compounds used to isolate structures from one another and reduce impact noise. These dense materials are used to block the transmission of airborne sound by providing mass to existing structures or hung as a limp mass partitions. Use these materials to soundproof walls, floors, and ceilings.
  43. 43. WALL COVERINGS: ◦ • Acoustical wall fabric is a dimensional fabric that offers excellent acoustical properties, unmatched fade resistance, and a fire/smoke retardant class A rating. Sound channels is resistant to moisture, mildew, rot, bacteria, and is non-allergenic. Produced with no voc’s (volatile organic compounds), ods’s (ozone depleting substances), heavy metals or formaldehyde, it's the perfect acoustic fabric for offices, classrooms, conference centers or any area where speech intelligibility is a critical factor. FEATURES: •Lightweight Acoustic Fabric •Easy to install •Class A •Passes Corner Burn Test •Available in Many Colors •Durable / Abuse Resistant •Improves Speech Intelligibility
  44. 44. WALL COVERINGS APPLICATIONS: •Conference Rooms •Theaters •Hospitals •Municipal •Office Partitions •Schools •Hallways and more... INSTALLATION: •This material is not factory trimmed. It is necessary for the installer to cut a straight vertical edge •Following the ribbed pattern. All edges must be butt joined. Do not overcut edges. Cut material to •Desired lengths, allowing for top and bottom trimming. Wall carpet should be hung •Straight up. Do not alternately reverse strips. •Apply a premixed heavy duty adhesive directly to the wall, allowing it to dry to its maximum tack ability •Without it being overly dry. (Important!!! Adhesives are ready mixed. Do not dilute) •Adhesive and do not apply adhesive to the back of the wall covering). •Please be sure to follow instructions as provided by the adhesive manufacturer.
  45. 45. ◦ CEILING TILES • Cloudscape® Ceiling Tiles absorb noise and block sound transmission. These ceiling tiles are designed to fit into existing 2' x 2' suspended drop tile ceiling grid systems. They may also retrofit in a 2' x 4' ceiling grid by installing cross tees. Cloudscape® ceiling tiles may also be ordered as a full 24" x 24" size, un-backed for adhesive mounting directly to walls or ceilings. • Ordinary ceilings take on new levels of visual excitement with these sculptured tiles. They are available in five different patterns plus a non-patterned look to enable you to "mix and match" for your own designs. Available Sizes: 24" x 24" (nominal) Specify grid when ordering: 9/16 or 15/16 BAFFLES AND BANNERS • Baffles and Banners are designed to solve acoustical problems economically in any large cubic volume space such as arenas, gymnasiums, theaters, restaurants, and auditoriums. Reverberation times that range from 4 to 9 seconds can be reduced to 1/2 to 2 seconds. Speech intelligibility is greatly improved and sound intensity levels are reduced simultaneously by 3 to 12 decibels. BAFFLES: • Baffles are an economical way to reduce sound pressure levels and lower reverberation times in large spaces such as gymnasiums, theaters, restaurants, healt h and fitness clubs, etc. Reverberation times can be lowered from a RT60 of 4 - 9 seconds down to a RT60 of 0.5 - 2 seconds. Speech intelligibility is greatly improved and sound intensity levels can be simultaneously reduced by 3 to 12 decibels. •These baffles are easily suspended from existing open truss and pre- engineered suspension systems. They are designed to hang in a vertical fashion, allowing free flow of air and integrate exceptionally well with existing sprinklers, lighting and HVAC systems. BANNERS: •Speech intelligibility is greatly improved and sound intensity levels can be simultaneously reduced by 3 to 12 decibels. •Banners are suspended from ceilings, bar joists or pre-engineered suspension systems. They are designed to hang in a horizontal or in a catenary fashion using edge stiffeners or deck mounted flat with washer plates
  46. 46. SOUND DIFFUSERS ◦ SOUND DIFFUSERS • These devices reduce the intensity of sound by scattering it over an expanded area, rather than eliminating the sound reflections as an absorber would. Traditional spatial diffusers, such as the polycylindrical (barrel) shapes also double as low frequency traps. Temporal diffusers, such as binary arrays and quadratics, scatter sound in a manner similar to diffraction of light, where the timing of reflections from an uneven surface of varying depths causes interference which spreads the sound. QUADRA PYRAMID DIFFUSER •This diffuser generates a uniform polar response over a broad frequency range using a pre-rotated pyramidal pattern to create 16 angles of reflection. PYRAMIDAL DIFFUSER •This traditional industry workhorse disperses sound uniformly over a broad frequency range. A quick solution to reduce flutter echo. DOUBLE DUTY DIFFUSER •These Polycylindrical Diffusers do twice the work. They scatter sound and function as a bass trap. QUADRATIC DIFFUSER ◦ A true quadratic residue diffuser designed for uniform broadband scattering and reducing High-Q reflections.
  47. 47. NOISE BARRIERS: ◦ NOISE BARRIERS ◦ These materials range from dense materials to block the transmission of airborne sound to devices and compounds used to isolate structures from one another and reduce impact noise. BARRIERS: •Sound barrier materials are used to reduce the transmission of airborne sound. The Block Aid® series of products include the standard one pound per square foot non reinforced barrier, transparent material when observation or supervision is required, reinforced vinyl to create a hanging barrier partition. COMPOSITES •Composite materials are manufactured from combinations of various materials from open and closed celled foams to quilted fiberglass and barrier. These products are used to block and absorb sound for machine enclosures as well as blocking airborne sound and impact noise. Some of these products include Composite Foams, Strati Quilt Blankets and Floor Underlayment. VIBRATION CONTROL •Vibration control products are used to absorb vibration energy and prevent structural noise transmission. These include vibration damping compounds and vibration pads, isolation hangers, and resilient clips. They improve sound transmission loss.
  48. 48. SOUND REFLECTORS ◦ FABRICS ◦ • Acoustical fabrics are typically used to either absorb sound or as a cover for acoustical panels. Some fabrics can also be used as a speaker grill cloth or as a finish on other types of materials. SOUND CHANNELS WALL FABRICS •Acoustical wall fabric is a dimensional fabric that offers excellent acoustical properties, unmatched fade resistance, and a fire/smoke retardant class A rating. Sound channels® is resistant to moisture, mildew, rot, bacteria, and is non- allergenic. Produced with no voc’s (volatile organic compounds), ods’s (ozone depleting substances), heavy metals or formaldehyde, it's the perfect acoustic fabric for offices, classrooms, conference centers or any area where speech intelligibility is a critical factor. GUILFORD OF MAINE •Guilford of Maine® Fabric is and acoustically transparent fabric used to cover many of our products including acoustical wall panels, diffusers, and corner traps. Fabric is also sold separately as speaker grill cloth, wall covering and for other field applications.
  49. 49. GLASS :
  50. 50. GLASS : ◦ Glass is an amorphous (non-crystalline) solid which is often transparent and has widespread practical, technological, and decorative usage in things like window panes, tableware, and optoelectronics. The most familiar, and historically the oldest, types of glass are based on the chemical compound silica (silicon dioxide), the primary constituent of sand. Main types of glass -Annealed glass -Toughened glass -Laminated glass -Coated glass -Mirrored glass -Patterned glass
  51. 51. ◦ Annealed glass: -Annealed glass is the basic flat glass product that is the first result of the float process. -It is common glass that tends to break into large, jagged shards. -It is used in some end products and often in double-glazed windows. -It is also the starting material used to produce more advanced products through further processing such as laminating, toughening, coating, etc. Toughened glass -Toughened glass is made from annealed glass treated with a thermal tempering process. (A sheet of annealed glass is heated to above its "annealing point" of 600°C; its surfaces are then rapidly cooled while the inner portion of the glass remains hotter. -The different cooling rates between the surface and the inside of the glass produces different physical properties, resulting in compressive stresses in the surface balanced by tensile stresses in the body of the glass.) -Toughened glass is treated to be far more resistant to breakage than simple annealed glass due to counteracting stresses and to break in a more predictable way when it does break, thus providing a major safety advantage in almost all of its applications. -Car windshields and windows, glass portions of building facades, glass sliding doors and partitions in houses and offices, glass furniture such as table tops, and many other products typically use toughened glass.
  52. 52. ◦ LAMINATED GLASS: Laminated glass is made of two or more layers of glass with one or more "interlayers" of polymeric material bonded between the glass layers. Rather than shattering on impact, laminated glass is held together by the interlayer giving more safety as well as, to some degree, reducing the security risks associated with easy penetration. The interlayer also provides a way to apply several other technologies and benefits, such as colorings, sound dampening, resistance to fire, ultraviolet filtering and other technologies that can be embedded in or with the interlayer. ◦ COATED GLASS: Surface coatings can be applied to glass to modify its appearance and give it many of the advanced characteristics and functions available in today's flat glass products, such as low maintenance, special reflection/ transmission/ absorption properties, scratch resistance, corrosion resistance, etc. Coatings are usually applied by controlled exposure of the glass surface to vapours , which bind to the glass forming a permanent coating. The coating process can be applied while the glass is still in the float line with the glass still warm, producing what is known as "hard-coated" glass.
  53. 53. ◦ MIRRORED GLASS To produce mirrored glass, a metal coating is applied to one side of the glass. The coating is generally made of silver, aluminium, gold or chrome. For simple mirrored glass, a fully reflective metal coating is applied and then sealed with a protective layer. To produce "one-way" mirrors, a much thinner metal coating is used, with no additional sealing or otherwise opaque layer. Mirrored glass is gaining a more prominent place in architecture, for important functional reasons as well as for the aesthetic effect. ◦ PATTERNED GLASS Patterned glass is flat glass whose surfaces display a regular pattern. The most common method for producing patterned glass is to pass heated glass (usually just after it exits the furnace where it is made) between rollers whose surfaces contain the negative relief of the desired pattern(s). Patterned glass is mostly used in internal decoration and internal architecture.
  54. 54. ◦ GLASS FOR GREEN BUILDINGS: Reflective glasses come with reflective coating that filters heat and let optimum light into the building. Reduce the heat gain inside the building, and thus reduces electricity and cooling costs. Allow optimum light (natural daylighting) inside the building, and thus reduces the cost for artificial lighting DIFFERENT USES: Supply of natural daylight Protection from rain, wind, and cold Transparency or translucency Means of communication Heat protection Sound protection Object and personal protection Fire protection Temporary heat and solar protection Use of solar energy Means of design Electromagnetic dampening.
  55. 55. ◦ STRONG BACK SYSTEM: The structural systems are the simplest form of structural support for a glass wall, but are only useful in relatively short spans of two to six meters usually. These systems can include both vertical and horizontal structural components. Sometimes verticals are used with no horizontals. They can be comprised of simple steel or aluminum open or closed sections with provisions for the attachment of the glazing system usually of spider type. ◦ TRUSS SYSTEM: Truss systems employ a planar truss design, often in a hierarchical system that may combine other element types including tension components. Truss designs vary widely, with an emphasis on fine detailing and craftsmanship. Rod or cable elements may be incorporated into the truss design, and lateral tensile systems are often used to stabilize the facade structure. ◦ CABLE TRUSS: One type of truss system utilizes a minimalist structural form called a cable truss. The main spinal compression element is removed, leaving the spreader struts as the sole compression elements in this truss type. As with cable nets, these systems rely on the pre-tensioning of truss elements to provide stability, and thus benefit significantly from the early involvement of the facade design/build team. STRUCTURAL GLASS SYSTEMS: Structural glass facades are most easily categorized by the structure types that support them.
  56. 56. ◦ GRID SHELLS: Grid shell structural systems are another means to minimize the visual mass of structure. Configurations can be vaulted, domed and double-curved. Systems can be welded, bolt-up, or some combination of each. Grid shell structures with integrated cable bracing can produce a highly efficient structure with a refined aesthetic. Grid shells can be used in vertical and overhead applications, as well as to form complete building enclosures. ◦ CABLE NET: If the spreaders were also to be removed from Cable Truss System, a system known as cable net is subsequently achieved. The glass is supported by a net geometry of pre-tensioned cables. A clamping component locks the cables together at their vertices and fixes the glass to the net. ◦ GLASS FINS: This technology was popularized by the Willis Faber & Dumas Building, Ipswich, England circa 1972. In this glass plates are suspended and laterally stiffened by the use of glass fins set perpendicular to the plates at the vertical joints between them.
  57. 57. ◦ SIGNIFICANCE: Glass is the dominating material in modern day architecture which places optical emphases and provides for numerous technical functions. The glass industry offers glazing with individual technical features that can be used for heat, solar, or sound protection, as design components, safety glass, or as a part of building design systems. Glass is no longer just a filler element, but is rather nowadays also used for supporting or enveloping purposes. The main focus in building is usually on saving energy, especially in these challenging times of increasing prices for energy and raw materials. Glass plays an important role in it. Hence promoting the concept of Sustainability. ◦ CONCLUSION: Over a period of time, Glass has acquired a special status as a significant building material. Apart from being a building material it is used in various forms also in the building to enhance the overall quality e.g. in furniture, electrical appliances and decorative items. Various technological innovations have made it a preferred choice for architects and designers to promote sustainability in built environment.
  59. 59. INTRODUCTION • Composite panels are a pre fabricated insulated building material with typically two metal skins bonded to an inner insulation core. • Some are available with plastic or fabric lining instead of metal for one or both skins. Such panels are in widespread use in modern buildings, either externally as wall or roofing material, or internally as compartmentation or linings. • They are an inexpensive, light and easy to install product with superior insulation and hygiene qualities to many similar building materials.
  60. 60. ◦ Panels are manufactured on a continuous lamination basis with metal facings - usually steel or aluminum - encapsulating a foamed polyurethane core. This composition offers a high degree of stability, rigidity and excellent load-bearing capacity. ◦ The thickness of the polyurethane foam can range from 30mm to 200mm depending upon application and required insulation characteristics. ◦ These versatile products are also known as 'sandwich' panels due to the physical interaction of the two materials.
  61. 61. SANDWICH PANEL ◦ A sandwich panel is a structure made of three layers: low density core inserted in between two relatively thin skin layers. • This sandwich setup allows to achieve excellent mechanical performance at minimal weight. • The very high rigidity of a sandwich panel is achieved thanks to interaction of its components under flexural load applied to the panel: core takes the shear loads and creates a distance between the skins which take the in-plane stresses, one skin in tension, the other in compression.
  62. 62. Panel feature Construction benefit Single manufactured unit Fast on-site erection = labor cost savings Allows fast project completion Minimizes on-site impact on product quality High insulation value at low panel thickness Reduced energy costs for life of building Dimensional space savings Greater saleable/leasable building area Structural value Combined air/ water barrier Long span, high load construction performance Material cost savings Ease of construction Removable panels Design/refurbishment flexibility Low maintenance Low whole life costs for building owner/tenant Surface treatments: texture and profiling Design/appearance flexibility Features and benefits of composite panels
  63. 63. ADVANTAGES ◦ This is a qualitative, aesthetic, reliable, multipurpose building material. ◦ Recently a number of materials which have instantly won popularity in all spheres and directions of the building industry, having superseded the traditional designs applied for many years. • Sandwiches-panels (a cassette profile) have proved as the universal material representing a basic element in building of any of buildings - from apartment houses to huge trading-entertaining complexes, stadiums, the medical centers, economic and industrial structures.
  64. 64. ◦ Reduction of cost of a building (from 30 to 50 %). Easy and easily transported panels have an original design which gives them special value. • Low heat conductivity of a material and small degree of moisture absorption. • Stability to ignition, simplicity of installation and assemblage a panel sandwich. • Allowing easily to assort small sites and to replace the damaged panels new, profitability of building process at the expense of absence of necessity to apply a special equipment at many stages of works.
  65. 65. WORKING OF PANELS ◦ The growth in use of composite panels has been driven by the construction industry's need for a lightweight panel with high thermal insulation values and simple on-site installation. ◦ The ease of mounting composite panels to the building sub-structure is another major factor in the popularity of this product. Building times are significantly reduced compared to traditional methods, with spin-off savings in labor costs.
  66. 66. EFFECT ON ENVIRONMENT The choice of composite panels as a building solution supports important environmental considerations. From an environmental perspective composite panels are: ◦ outstanding providers of thermal insulation; reducing heating and cooling costs for the lifetime of a building; ◦ long life applications, maximizing natural resources used in manufacture; ◦ contributing to reduced emission of greenhouse gases - in production, transportation and installation.
  67. 67. HONEYCOMB SANDWICH PANEL ◦ Honeycomb sandwich panel has been proven as the most efficient sandwich design with respect to mechanical performance and weight. ◦ Aerospace and aircraft industry uses the honeycomb structures as they meet the tough requirements of related applications. The use of honeycomb sandwich design in more common applications has been more limited due to the batch wise manufacturing processes and hence relatively high production costs.
  68. 68. ALUMINIUM COMPOSITE PANEL ◦ Aluminium composite panel (ACP), also aluminium composite material (ACM), is a type of flat panel that consists of two thin Aluminium sheets bonded to a non-aluminium core. ◦ ACPs are frequently used for external cladding or facades of buildings, insulation, and signage. If the core material is flammable, usage may be problematic as a building material and some jurisdictions have banned their use. • Aluminium sheets are coated with polyvinylidene fluoride (PVDF), fluoropolymer resins (FEVE), or polyester paint. Aluminium can be painted in any kind of color, and ACPs are produced in a wide range of metallic and non-metallic colors as well as patterns that imitate other materials, such as wood or marble. The core is commonly low-density polyethylene, or a mix of low-density polyethylene and mineral material to exhibit fire retardant properties.
  69. 69. • ACP as a construction material ACP is mainly used for external and internal architectural cladding or partitions, false ceilings, Sign trays, Individual logos, Column cladding, Counter cladding, Grilles and screens, Machine parts and covers, Display panels, etc. External architectural cladding.
  70. 70. APPLICATIONS ◦ Sandwich panels are used in applications where high structural rigidity and low weight are required. An evident example of use of sandwich panels is aircraft, where mechanical performance and weight saving is essential. ◦ Other applications include packaging (e.g. fluted polypropylene boards of polypropylene honeycomb boards), transportation and automotive as well as building & construction. ◦ ACP is mainly used for external and internal architectural cladding or partitions, false ceilings, signage, machine coverings, container construction, etc. Applications of ACP are not limited to external building cladding, but can also be used in any form of cladding such as partitions, false ceilings, etc. ACP is also widely used within the signage industry as an alternative to heavier, more expensive substrates.
  71. 71. ◦ ACP has been used as a light-weight but very sturdy material in construction, particularly for transient structures like trade show booths and similar temporary elements. ◦ It has recently also been adopted as a backing material for mounting fine art photography, often with an acrylic finish using processes like Diasec or other face-mounting techniques. ◦ ACP material has been used in famous structures as Spaceship Earth, VanDusen Botanical Garden, the Leipzig branch of the German National Library. ◦ These structures made optimal use of ACP through its cost, durability, and efficiency. Its flexibility, low weight, and easy forming and processing allow for innovative design with increased rigidity and durability. Epcot's Spaceship Earth is an example of the use of ACP in architecture. It is a geodesic sphere composed of 11,324 ACP tiles.
  73. 73. GYPSUM BLOCK ◦ Gypsum block is a massive lightweight building material composed of solid gypsum, for building and erecting lightweight fire-resistant non-load bearing interior walls, partition walls, cavity walls, skin walls and pillar casing indoors. ◦ Gypsum blocks are composed of gypsum plaster, water and in some cases additives like vegetable or wood fibre for greater strength. ◦ Partition walls made from gypsum blocks require no sub-structure for erection and gypsum adhesive is used as bonding agent, not standard mortar.
  74. 74. ◦ The dimensions of these blocks are: length 500 mm, height 500 mm. Four blocks thus make 1 m². ◦ Gypsum blocks vary in thickness - 2", 3", 4" and 6“. For construction purposes especially two densities are important: ◦ The medium gross density of 850 kg/m³ to 1.100 kg/m³ (white coloured blocks, suitable for standard usage) ◦ The high gross density blocks of 1.100 kg/m³ to 1.500 kg/m³ (reddish colour, suitable for walls with higher acoustic performance requirements) SPECIFICATIONS
  75. 75. PROPERTIES Gypsum blocks combine the advantages of classical masonry with modern drywall construction. Similar to masonry, walls built with gypsum blocks are massive, void-free and of high stability. Because no mortar, sand or plaster are used, the walls are (almost) built without water, like drywalls. Fire resistance ◦ Massive gypsum blocks have a high level of passive fire protection: 60 mm thickness offers 30 minutes of fire resistance (F30-A in accordance with the German DIN 4102 standard, the European EN 13501 or the British BS 476); 80 mm thickness offers 2 hours of fire resistance Sound proof ◦ To improve the sound proof qualities of gypsum block partition walls, insulation strips are used on all sides to connect the partition walls to adjacent walls, ceilings and floors. The acoustic decoupling of the walls in this way reduces the acoustic transmissions of these lightweight partition walls significantly.
  76. 76. APPLICATION ◦ Gypsum blocks are for use internally, as partition walling in all kind of building constructions e.g. flats, dwellings, industrial buildings, offices, hospitals, schools, nursing homes etc. DESIGN AND COMPOSITION ◦ Rectangular, smooth solid gypsum blocks, manufactured from high-quality plaster, water and in some cases additives. CONCERN ◦ Never use in areas in which moisture exposure could occur GYPSUM BLOCK
  77. 77. Metals are solid materials that exist in nature. Their properties include: • Good electrical and thermal conductivity • High strength, • High stiffness • Good ductility • Malleable • Some metals, such as iron, cobalt and nickel are Magnetic • Fusible METALS PURE METALS ALLOYS Elements which comes from a particular area of the periodic table. E.g. Copper in electrical wires and Aluminium in cooking foil and beverage cans. Contain more than one metallic element. E.g. Stainless steel, alloy of iron, nickel, and chromium; Gold jewelry , alloy of gold and nickel. METALS INTRODUCTION
  78. 78. USAGEIN CONSTRUCTION INDUSTRY  Metal is used as structural framework for larger buildings such as skyscrapers,  or as an external surface covering.  There are many types of metals used for building.  Metal figures quite prominently in prefabricated structures and can be seen used in most cosmopolitan cities.  Steel is a metal alloy whose major component is iron, and is the usual choice for metal structural building materials. It is strong, flexible, and if refined well and/or treated lasts a long time.  The lower density and better corrosion resistance of aluminium alloys and tin sometimes overcome their greater cost  Copper is a valued building material because of its advantageous properties.  These include corrosion resistance, durability, low thermal movement, light weight, radio frequency shielding, lightning protection, sustainability, recyclability, and a wide range of finishes.  Copper is incorporated into roofing, flashing, gutters, downspouts, domes, spires, vaults, wall cladding, building expansion joints, and indoor design elements.  Other metals used include chrome, gold, silver, and titanium.  Titanium can be used for structural purposes, but it is much more expensive than steel.  Chrome, gold, and silver are used as decoration, because these materials are expensive and lack structural qualities such as tensile strength or hardness. • It requires a great deal of human labor to produce metal, especially in the large amounts needed for the building industries. • Corrosion is metal's prime enemy when it comes to longevity.