GLASS AS A BUILDING MATERIAL

GLASS AS A BUILDING MATERIALGlass has become one of the most popular and complex building materials used today by offering virtually unlimited aesthetic options, combined with outstanding performance.PROPERTIES OF GLASSThe properties of glass are mainly governed by factorssuch as composition of the constituents, state ofsurface, thermal treatment conditions, dimensions ofspecimen, etc.The following are the properties of glass which havemade glass popular and useful.(1) It absorbs, refracts or transmits light.(2) It can take up a high polish and may be used as substitute for every costly gems.(3) It has no definite crystalline structure.(4) It has no sharp melting point.(5) It is affected by alkalis.

6) It is an excellent electrical insulator at elevated temperatures due to the fact that glass can be considered as an ionic liquid. (8) It behaves more as a solid than most solids in the sense that it is elastic. But when the elastic limit is exceeded, it fractures instead of deforming.(9) It is capable of being worked on in many ways.(10) It is extremely brittle.(11) It is not usually affected by air or water.(12) It is not easily attacked by ordinary chemical reagents.(13) It is possible to intentionally alter some of its properties such as fusibility, hardness, refractive power, etc. to suit different purposes.(14) It is possible to obtain glass with diversified properties. The glasses may be clear, colorless, diffused,colored and stained.(15) It is possible to weld pieces of glass by fusion.(16) It is transparent and translucentTYPES OF GLASS

A few examples of glass include:Annealed Glass; this is the most common architectural glass

Prism glass; it is glass used to provide lighting to underground spaces and areas that would otherwise be too difficult to light.

Glass block; also known as Glass brick is used in areas where privacy or visual obscuration is desirable while admitting light such as; underground

Frosted glass; it is glass which has been rendered opaque through a process which roughens or obscures the clear surface of the glass. It is produced by the sandblasting or acid etching of clear sheet glass.

Stained glass; this is glass that is coloured as a material. As a material, it is coloured by adding metallic salts during its manufacture

USES OF GLASS IN CONSTRUCTIONGlass is one of the construction materials usedin buildings and below are the various uses:Glass panes in windows

Curtain walling

Partitioning

Balcony railing

Roof Construction

Doors

Used in bathroomsFrosted glass is used on bathroom windows to allow light but not visibility ,it is also used in steam rooms and shower cubicles

Disadvantages of glassAs glass is a very costly material, it may increase the budgeted cost of construction work.

Use of glass also enhances the cost of security.

Glass also comes with the disadvantage of being heavier and more difficult to handle as it is easily breakable.

Installing glass is labor-intensive because it must be set panel-by-panel.

Melts in high temperatures.

Low strength; so unable to share the stress loads. For instance, tall, slender glass buildings would break under their own weight

Transmits radiant heat; so interiors can gain heat from outside sources (like the Sun) or lose heat when the outside is cold. Thus, a steady interior temperature is harder to maintain unless special technologies are invoked (like window blinds).

Difficult to work with if irregular shapes are needed. Glass is malleable only when heated and treated in special kilns and by special tools.

Glass in high buildings is a constant threat to people below who might be underneath a falling glass pane or its shards. This is a not infrequent happening during earthquakes in a city with high-rises. Glass is also unsafe for earthquake proven area.

SOLUTIONS AND CURRENT TRENDS IN GLASS

Thermal insulation A transparent metallic coating reflects heat back into the room rather than allowing it to escape through the windows. At the same time, it allows solar heat to pass into a building and warm the interior.

Solar controlSolar control glass is glass designed to reduce or prevent solar heating of buildings. There are two approaches that can be used: The glass is either tinted (colored) throughout the material (called a "body tint") or it has a microscopically thin and transparent coating on one side.

Safety and securityTo improve its resistance to impact and breakage, glass can be either toughened or laminated, depending on where and how it is being used.Below is an example of laminated glass.

Wired glassWire mesh glass has a grid or mesh of thin metalwireembedded within the glass.Despite this belief, wired glass is actually weaker than unwired glass due to the incursions of the wire into the structure of the glass. Wired glass instead is utilized for itsfire-resistantabilities, and is well-rated to withstand both heat and hose streams.

Self cleaning glassSelf cleaning glass has been coated with a special dual function layer that harnesses the elements to which windows and facades are exposed - namely the sun and rain - to break down and wash away dirt. This first function is photo-catalytic; in other words, it is activated by light to break down the dirt that collects on it. The second function is to spread rain water evenly over the glass. Noise controlAcoustically insulating glazing can be a major contributor to comfort levels in buildings and houses. Its benefits are greatest for people living or working near busy high streets, urban traffic, motorways, railway lines and airports, or on a flight path. The acoustic glass in a double-glazed unit uses a special interlayer that acts as a dampening core so that sound energy is effectively blocked from passing from the outside to the inside pane of glass.

CONCLUSIONIt can thus be easily appreciated that glass, though used for thousands of years, is just beginning to be understood and it is still possible to get a variety of glasses with certain chemical additives.We recommend the use of glass as it offers a variety of functions and at the same time its aesthetic value.