There is a special relationship between glass and buildings. Glass is a magical material which has so many different properties and uses, that it has presented Architects with many new possibilities and designs. In their quest for transparency and safety, Architects often use reinforced, toughened and laminated glasses.
History of Glass Blocks used in Construction
In the early 1800’s, individual glass blocks were used to provide light to cellars and ships’ bowels – at first, cut squares of simple conventional glass, then prism-shaped pressed glass which allowed light to be dispersed. In order to fix this prismatic glass, they were fitted into steel frame structures in the form of intermediate ceilings or skylights which allowed larger surfaces to become translucent.
In 1904, Joachim, a French architect, built the first dome of concrete and glass.
The development of hollow glass blocks for vertical structures, which offered the advantage of better noise and thermal isolation in comparison to the solid blocks, took place at the same time. Glass blocks are manufactured in different sizes and patterns in accordance with the various requirements and applications. The present commercial method of manufacturing allow glass blocks with a maximum surface of 30cm x 30cm to be produced. They are used to produce straight and curved interior and exterior walls.
Why are Glass blocks used?
Glass has the following properties…
Beauty & Versatility
Extraordinarily versatile and available in many aesthetically pleasing sizes and styles, glass block offers virtually limitless design possibilities. Glass block walls, partitions and window combine the delicate beauty and light transmission of glass with the strength of glass block. Glass can be made available in several colors. When we combine single sheets of glass in laminated or insulated units, they typically change in overall color and appearance. Glass color appearance can be also conditioned by several environmental factors such as sunlight (midday sun or sunset), reflected sky and clouds.
Visibility & Light Transmission
Glass block provides exceptional visibility. It is also scratch-resistant, and transmits up to 80% of available light in both directions without any yellowing, clouding or weathering.
Glass is a bad conductor of heat.. A good double layered glass acts as a good insulator, and thus can help in the conservation of Energy and reducing your power bills. Lower heat-loss is achieved by multiple glazing layers, gases and the use of low-e coatings.
Sealed glass panes transmit very little sound, and hence can be a good sound insulator. The most common types of glass used are laminated and insulating glass (Double glazed). Laminated glass incorporates a special acoustic PVB interlayer, which absorbs some of the incident sound energy, reducing its passage. Better sound insulation can also be achieved with double-glazed glass in which vacuum-sealed inner spaces and some gases affect sound insulation and provide acoustic stability.
Special types of Bullet and blast resistant glass is available that does not shatter, but rather absorbs the projectile energy, thus protecting the inhabitants of the structure. It is basically made by layering a polycarbonate material between pieces of ordinary glass in a process called lamination. This process creates a glass-like material that is thicker than normal glass.
Glass block panels are non-load bearing; adequate provisions must be made for support of construction above these panels. Panels are mortared at the sill, with jamb and head details designed to provide for building movement and lintel deflection.
Plain Glass used for the Building Facade
Glass Blocks used for the Building Facade
Types of Glass used in the Architectural Field
It is the commonest type of glazing glass available. It may also be used for Door and window partitions. It is used by drawing a sheet from liquified ball of glass.
It is used for general glazing purposes in windows, shop fronts, buildings and workshops. Also used for sales counter and table tops after being laminated with plywood or metal sheet.
Wired glass is a product in which a wire mesh has been inserted during production. It has an impact resistance similar to that of normal glass, but in case of breakage, the mesh retains the pieces of glass. This product is traditionally accepted as low-cost fire glass. Can be used for Skylights and North Light trusses, fire-resisting doors and windows.
Laminated glass is a type of safety glass that holds together when shattered. In the event of breaking, it is held in place by an interlayer, typically of polyvinyl butyral (PVB), between its two or more layers of glass. The interlayer keeps the layers of glass bonded even when broken, and its high strength prevents the glass from breaking up into large sharp pieces. It is normally used when there is a possibility of human impact or where the glass could fall if shattered. Skylight glazing and automobile windshields typically use laminated glass.
This is a special type of glass having high refractive index. It is used for making lenses, table ware, cut glass wares, electric tubes, radio valves and optical glass. Also may be used in electric lamps, thermometers, electron tubes, laboratory apparatuses, containers for food… etc.
It is a plain glass which has a rough, matte finish. It could be used for window panes and bathroom ventilators and at such places where diffused light is required.
This special cellular glass has high heat and sound insulation properties. It is lightweight, opaque glass material having a closed-cell structure. Foam glass is light enough to float in water and is impervious to moisture, most fumes, and vermin.
Fiberglass is material made from extremely fine fibers of glass. It is used as a reinforcing agent for many polymer products. Sometimes, it is also known as fiber-reinforced polymer (FRP) or glass-reinforced plastic (GRP). It is tough and durable, and is used in a variety of places, such as in the manufacture of glass based roofing, for insulation of pipes, bends, valves etc, thermal insulation of containers and panel insulation.