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What is Glass? Glass is known for its fragility as well as firmness that makes it typical of a solid. At the same time, it can be qualified as a liquid, owing to its somewhat fluid nature. But, scientifically, glass is what is called an amorphous solid – a state between two states of matter. In terms of conductivity, glass has neither thermal nor electrical, since it has no reaction with the commonly known chemical compounds. What is Glass Made of? The primary raw materials in glass are sand, soda, limestone, clarifying agents, coloring and glistening glass. Glass sand is about ¾th of the entire glass composition. How is Glass Produced? A float line is almost like a river of glass that exits the furnace before its cooling process. It makes its way to nearly 300 meters, after which it is cut into large sheets; these sheets typically measure 3.21x2.25 meters. Hence a float line is capable of continuously producing glass round-the-clock. Float Glass Float glass, commonly known as flat glass, is made by floating molten glass on a bed of molten tin. The molten glass spreads onto the surface of the metal and produces a high quality, consistently level sheet of glass that is later cut into required sizes. This method gives the glass uniform thickness and a very flat surface. The glass manufactured thus is devoid of waves or distortion. This technique can continuously produce glass 24/7. It is therefore a river of glass that exits the furnace before being cooled as it progresses along its path of around 300 meters and is then cut into very large sheets, which most frequently measure 3.21x2.25 meters. The float glass production process can be divided into five universal steps: 1.Batching of raw materials: The main components, comprising silica sand, calcium oxide, soda & magnesium are weighed and mixed into batches to which recycled glass (cullet) is added. The use of ‘cullet’ reduces the consumption of energy. The materials are tested and stored for mixing later under computerized control. The superior clarity offered by Saint-Gobain Clear Glass, is a result of purity in raw materials, precision in composition and strict adherence to high quality standards in the manufacturing process. The company has a dedicated sand beneficiation plant in Tada where silica sand (to be used in manufacturing) is purified, and excess iron content is removed from the material. 2.Melting of raw materials in the furnace: The batched raw materials pass from a mixing silo to a five-chambered furnace where they become molten. Temperatures in the furnace reach upto 1600°C. 3.Drawing the molten glass onto the tin bath: The molten glass is then "floated" onto a bath of molten tin at a temperature of about 1000°C. It forms a “ribbon” which is normally between 5 and 6 mm. By suitably drawing the glass through a complex process involving top roll machines, ribbon thickness in the range of 1.9mm to 19mm can be achieved. The glass, which is highly viscous, and the tin, which is very fluid, do not mix and the contact surface between these two materials is perfectly flat, giving the term “flat” glass to the final product. 4.Cooling of the molten glass in the annealing lehr: On leaving the bath of molten tin, the glass - now at a temperature of 600°C - has cooled down sufficiently to pass to an annealing chamber called a lehr. The glass is now hard enough to pass over rollers and is annealed, which modifies the internal stresses, enabling it to be cut and worked in a predictable way and ensuring flatness of the glass. As both surfaces are fire finished, they need no grinding or polishing 5.Quality checks, automatic cutting, and storage: After cooling, the glass undergoes rigorous quality checks. It is then cut into sheets of sizes varying upto a maximum of 6000mm x 3660 mm which are, in turn, automatically stacked, stored and ready for transport. Applications Float glass is used for glazing wherever full transparency is required in buildings. It is used as a base material for safety glass, reflective glass and self-cleaning glass, among others. It can be used in precision mechanics, especially where extreme surface flatness is required. E.g., for visual displays. 654PPM Saint-Gobain Glass is known for the lowest iron content (654 Parts Per Million) which makes it the clearest glass in its category (lower the iron content, clearer the glass). With unmatched purity and extreme clarity, this glass is used as the base for manufacturing its other products and has wide-ranging applications. It is also the base for Saint-Gobain's 'Glass-Shield', a new initiative by the company to facilitate safety and social distancing for a post-pandemic world Get in touch

Toughened glass is a safety glass that has undergone processes of controlled thermal treatment to increase its strength. Also known as 'Tempered glass', toughened glass is made from annealed glass that has been heated to approximately 650⁰C and then rapidly cooled, making it four times stronger than the ordinary glass. Due to the increased heat treatment and rapid cooling of the glass, the treatment produces different physical properties. This results in compressive stress on the surface and improved bending strength of the glass. Before toughening, the glass must be cut to the correct size or pressed to shape. The Process of Toughening The glass is carried by rollers and goes through the furnace. Three types of modes are used to heat the glass - conduction, convection and radiation. While the rollers help to conduct the heat, the coils enable radiation of heat. This ensures that the glass is evenly heated on every side. By blasting air on both the surfaces, the heated glass is then cooled uniformly. .iframe-purpose iframe{ Width:100%; } Characteristics of Toughened Glass After toughening, glass can neither be cut, nor altered. Toughening does not alter the basic characteristics of glass - like light transmission or solar heat reflection. Glass toughened is known to have higher thermal strength, with the ability to withstand high temperatures up to 250°C. Toughened glass is difficult to break but in the event of a breakage, disintegrates into small, harmless blunt pieces. Saint-Gobain Toughened Glass Watch more Toughened glass videos here. Toughened Glass Vs Ordinary Glass Parameters Toughened Glass Ordinary Glass Strength Known for its strength and durability Brittle and lacks endurance Breakage Pattern Does not break easily; In the rare event of breakage, shatters into small, pebble-like pieces Breaks under pressure; Breakage results in dangerous, jagged edges Safety Offers greater safety due to its resilience Relatively unsafe due to its delicate nature Flexibility Can’t be altered after tempering Can be cut, drilled, or polished Application area Appropriate for high-traffic areas Inappropriate for high-traffic areas Benefits of Toughened Glass Toughened glass has high withstanding capacity and is therefore suitable for uses where strength and thermal resistance are crucial. It is nearly four to five times stronger than annealed glass, and thrice as strong as heat strengthened glass. Even during breakage, its relatively small pieces reduce the chances of injury. While annealed glass is susceptible to thermal breakage with drastic changes in temperature, toughened glass has higher edge strength to resist thermal breakage. Toughened glass is ideal in spider and point fixed glazing owing to its high edge strength. Toughened glass is preferred because of the protection it offers, be it for the elderly or children, creating a safety blanket unlike ordinary glass. What makes tough glass the go-to choice is the sturdiness it ensures, and its capacity to not break under pressure; even if it does break, which is extremely rare, the pieces are not sharp or jagged that tend to cause serious injury. Toughened glass can also be made acoustic, allowing privacy and peace in the living space. Functional advantages aside, toughened glass is also an interior designer's delight as it enables one to add to the aesthetic value with its myriad styles. From protection to privacy, from durability to designing options, Toughened glass has become an integral part of homes. With homes and interior spaces opening up new avenues and newer applications in glass, Saint-Gobain Toughened Glass adds value with its blend of aesthetic and functional advantages. Explore Saint-Gobain Assured processors Frequently Asked Questions The glass is carried by rollers and goes through the furnace. Three types of modes are used to heat the glass - conduction, convection and radiation. While the rollers help to conduct the heat, the coils enable radiation of heat. This ensures that the glass is evenly heated on every side. By blasting air on both the surfaces, the heated glass is then cooled uniformly. What is toughened glass? Glass that has been subjected to a controlled heating and cooling process, in order to significantly increase its resistance to mechanical and thermal stress. Through the thermal toughening process, the glass attains its safe-breakage characteristics. Is it possible to cut toughened glass? It is possible to cut and toughen a glass but after toughening glass cannot be cut. Is toughened glass good for home? Toughened glass is a prefered material for home to ensure added safety What are the benefits of toughened glass? Toughened glass has high withstanding capacity and is therefore suitable for uses where strength and thermal resistance are crucial. How does toughened glass break? In the rare event of breakage, toughened glass shatters into small, pebble-like pieces. How is glass toughened made? Toughened glass or tempered glass is the glass that has undergone processes of controlled thermal treatment to increase its strength. Which glass is used for balcony railing? Toughened glass is preferred for balcony railing. What is the difference between tempered glass and toughened glass? Although both the terms are interchangeably used, toughened glass is one kind of tempered glass. Can toughened glass be drilled? An ordinary glass can be drilled before toughening it. What type of glass is used for stairs? Toughened glass is preferred for stairs and staircase railing. What are advantages of toughened glass? Toughened glass has high withstanding capacity and is therefore suitable for uses where strength and thermal resistance are crucial. Why to choose toughened glass? Toughened glass has high withstanding capacity and is therefore suitable for uses where strength and thermal resistance are crucial. What can toughened glass be used for? Ideal for high-traffic areas, toughened glass can be used for all applications to ensure added safety. What are the different applications of toughened glass? Ideal for high-traffic areas, toughened glass can be used for all applications to ensure added safety. How to know if glass used is toughened or not? Look in the corners of the glass pane to see if there is an emblem stating it has been toughened/tempered. How to know if glass used is Saint-Gobain Glass? Look in the corners of the glass pane for Saint-Gobain Assured logo. For more details on Saint-Gobain Assured, click here

Glass and daylighting Natural light provides a sense of orientation, affecting our surroundings and marking the passage of time. Glass enables us to control and manipulate light to our advantage. "The sun is the great luminary of all that lives. It should be used as such in the design of every house” -Frank Lloyd Wright Daylight is the source of life and essential to our wellbeing, development and health. The great architects of every age have understood this, captivated and inspired by its necessity. Glass enables us to control and manipulate light to our advantage. A window is a link between interior environments, where we live and work, and the outside world. It can determine the quality of a building, in terms of both architectural design and interior ambiance. Building with Natural Light Light levels and their effect on interior spaces, can influence our daily activities and frame of mind. Some general suggestions are:  To open up areas where we spend much time during the day, such as kitchens, dining rooms, reception rooms and offices  To encourage natural light into areas of study and work, at home and in the workplace To ensure that rooms are properly ventilated, for health and hygiene reasons  To design houses or buildings so that all living areas have access to opening windows To take the external surroundings into account (nearby buildings, vegetation, natural features) To provide natural illumination from more than one direction wherever possible. Glazing on two opposite facades balances lighting levels, softens shadows and opens up the room space Aesthetic Drivers: There are two drivers of aesthetics: Visual light transmissionReflectionIt is defined as the percentage of the light transmitted through the glass.The reflection of the glass depends on the type of coating and also the position of the coating used on the glass, Lower external reflection helps in the true colour rendering of the building and it is normally suggested to have lower internal reflection to minimize the night time glare. Visual Comfort Most people spend much of their day either at work, at home or in an educational establishment. The quality of the light in their surroundings has considerable implications on their safety, health, state of mind and even their efficiency. The most important points to remember about natural lighting are as follows: Position work areas close to windows Facilitate visibility out of the building Avoid direct sunlight in work areas to minimize the associated problems associated with glare Distribute light evenly, avoiding strong areas of contrasts in the field of vision, which can result in problems associated with glare Get in touch

LOW-E GLASS FOR WINDOWS By significantly reducing heat loss, high performance thermal insulated glazing enhances the energy-efficiency of windows. Low-E coating is an almost invisible film of metal or metal oxide layers deposited on a window or skylight. It reduces U-factor by restricting radiative heat flow. Heat is transferred in multilayer glazing by way of thermal radiation from a warm sheet of glass to a cooler sheet. By covering a glass surface with a low-emittance element and placing that coating into the gap between the layers of glass helps in impeding the radiant heat transfer. This restricts flow of heat through the window. Benefits of Low-E Glass One of the biggest benefits of Low-E Glass is that it helps to minimize the direct and indirect heat gain through the facade. Under different weather conditions and climate zones, it helps to eliminate glare through the year. The coating on Low-E Glass is especially useful in reducing hazardous ultraviolet (UV) light. In colder climes, the interior heat tends to travel to the colder exteriors, but the coating on Low-E glass actually helps to reflect the heat back inside; this reduces the radiant heat loss. The reverse is likely to occur in warmer climate zones, and the coating helps to prevent the exterior heat to travel interiors. Therefore, Low-E Glass is equally relevant to both cold and warm climatic conditions. Low-E glass is compliant with Green rating norms, contributing to sustainable structures. Due to the functional metallic Low-E coating, higher visual light transmission is made possible while reducing the solar heat gain. It ensures increased energy-efficiency and cost reduction with the elimination of blinds and artificial lights. Diverse ranges of Window to Wall ratio are possible. There is clarity in vision and realistic views through façade panel and clear external view throughout the day. The result: increased productivity and occupant comfort. Recommended Products: Planitherm Nano Envision Xtreme Lunar Sky Quartz Equinox Wave Harmony Have a Query? Get in touch

Ceramic Fritting is a process by which glass enamel is fused on the glass surface. Before the glass is heat strengthened or tempered, Ceramic frit is applied to the glass through a fine mesh screen with glass enamel. After tempering or heat strengthening, the glass enamel becomes a permanent coating which cannot be further damaged or removed by cleaning, scrubbing, etc. Silk-screening is done by printing a layer of ceramic ink on the glass surface through a screen mesh. When silk-screened glass is combined with clear, tinted, Low-E, or reflective glass, it can control light transmittance and reduce solar heat gain while enhancing aesthetic and performance characteristics. Though normally suitable for IGUs, silk-screened glass can be used for both exterior and interior applications. When used on building exteriors, the painted surface must be protected from direct contact with the environment. Process Annealed glass is washed and Ceramic frit paint is applied to the interior of the glass Frit is made of tiny glass particles, pigments and various chemicals for the curing To create a permanent coating, Ceramic frit is fired within a tempering furnace To prevent glass breakage due to thermal stress, the glass is always heat strengthened or tempered Ceramic frit can be combined with clear or tinted glass substrates, and high-performance coatings to reduce glare and decrease solar transmission Features Light frit colors and some types of pattern designs cause enhanced brightness and dark frit colors reduce glare. Certain applications mask a part/whole of glass for privacy, hide the background, enhance the look of a product or used merely for aesthetics. The coating remains unaffected by moisture, oil, soaps, chemicals or detergents; it is capable of retaining its original appearance throughout the life of the glass. Applications Transparent and translucent silk-screened glass is ideal for interior applications, including glass doors, partitions, handrails, glass ceilings, bathrooms, elevator walls and shower enclosures. Ceramic frit glass can be used in curtain walls, point fixed or bolted glazing systems, shower installations, glass doors and partitions. Know more on Saint-Gobain Door know more on Saint-Gobain Partitions Know more on Saint-Gobain Glass Ceilings Know more on Saint-Gobain Shower Enclosure Have a Query? Get in touch

Insulated Glass combines two or more glass panes that are spaced apart and sealed with a sealant to appear as a single unit. Also called double glazing, IGUs are designed to reduce heat loss and solar heat gain entering the building, while reducing visible light transmittance. Hence they improve the thermal performance, and reduce energy costs. They can be fabricated to meet sound control requirements, seismic requirements, bullet resistance, hurricane and blast resistance requirements, impact resistance and state energy codes. By combining laminated glass products, tinted glass, Low-E coatings, reflective coatings, silk-screened patterns, etc., a wide variety of insulating glass configurations can be made available to meet diverse aesthetic and performance needs. IGU Surfaces The IGU comprises the following four surfaces: Surface 1 is the glass side that faces the building's exterior Surface 2 is other side of the Surface 1. Surface 4 is the glass side that faces the building's interior Surface 3 is the other side of surface 4. Process The various machines used in the process of making insulated glass are washing unit, drying unit, spacer conveyor, butyl extruder, and pressing unit, which is vertical. The insulated glass is constructed in the following ways: A hollow aluminium spacer bar is bent into the desired shape. Holes are drilled in the spacer bar, which is filled with a desiccant such as silica gel or zeolite that helps in absorbing water vapour. The drilled holes are sealed with a primary sealant such as butyl. Primary sealant is also applied to the sides of the spacer bar. Two glass panes are placed along the side of the spacer bar and pressed with an automatic presser. A secondary sealant such as polysulphide or silicon is applied along the sides of the whole unit. The insulating glass unit is ready. Components Glass lites: An IGU consists of at least two panes (or lites) of glass. Although IGUs generally use monolithic glass, other types of coated and laminated glasses may be used, depending on the application to enhance the performance of the unit Frame: To remove the moisture within the IGU, Desiccants are used. The different types of desiccants are silica, molecular sieve and zeolites. The desiccants should be able to absorb water and hydrocarbons, not absorb krypton, argon or other thermal performance gases and should not contain pre-absorbed nitrogen. Desiccant: Frame is the spacer bar that is used to separate the two glass lites in an IGU. It is usually made of aluminium and filled with desiccant. It is responsible for holding the unit together, providing thickness and mechanical resistance, and ensuring optimum performance of the unit. There are two types of frames: those that are joined with corner keys and those by bent frames. - In the first type, the spacer material is cut to the specific size and desiccant is filled. The four sides are then assembled together using corner keys. In this process, the heat loss is more since the frame created has four joints. To resolve this, the frame is bent at 90 degree angle and assembled with only one joint, called a bent frame. Sealant: Sealants are integral to manufacturing insulating glass because of their efficiency, ease of handling, eco-friendliness and safety. They are known for their adhesion, elasticity and durability. They also have a good cure profile, with low moisture vapour transmission rates. Sealants are of two types: primary and secondary. Poly Iso Butylene, or Butyl, is the most common primary sealant used. Silicone and Polysulfide are commonly used secondary sealants. The primary sealant helps in fixing the IGU at the time of assembly. Secondary sealant protects the gas filled spaces from moisture vapour penetration, chemical attack from cleaning fluids and glazing products, and liquid water penetration due to rain or condensation. Secondary sealants are structural adhesives, binding the glass panes in multi-pane IGUs (MIG) together. The sealant comprises two components which are mixed before application and applied either manually or mechanically. Filling: There are three different types of IGUs based on the type of gas filled between the glass lites. The most commonly used type is the regular IGU with no filling - it has dry air inside The second type is the one with inert gas filling. Inert gases such as argon, krypton, and xenon are used as a filling in this type of IGU. They are more efficient than dry air, but expensive The third type of IGU is where vacuum exists between the glass lites The formula used to calculate the amount of gas to be filled into the IGU is: Height (cm) x Length (cm) x ID (mm) x 0.001 = Number of Litres (x) Number of Litres (X) x 1.5 = Number of Litres of gas required per window Features Optical properties: The visible light transmittance of insulating glazing systems typically ranges between 7% and 80% while the visible light reflectance is in the range of 13-48%. Thermal Properties: The U value is effectively lowered by insulating glazing; it can be further reduced by filling of inert gases. Acoustical insulation: Insulating glazing can reduce noise by about 30dB and further reduction can be achieved by filling of inert gases and using laminated glazing. Condensation: The dew point of CSG insulating glazing systems is below-65C. It assures of no condensation formation under normal applications. Sealing: Aluminum spacer frame is automatically curved and formed with only one joint and two seals are applied in insulating glass production. This ensures excellent sealing characteristics and long application life-time. Benefits Energy Conservation: Monolithic glass Insulating glass Monolithic glass is a single glass. Eg. annealed glass Double glass contains hermetically sealed dry air space between the sheets of glass. Eg. IGU Gets heated directly by sunlight. Double glazing prevents direct contact with sunlight. Breakage Pattern Does not break easily; In the rare event of breakage, shatters into small, pebble-like pieces With the use of air-conditioner,the temperature difference between the inside and outside the building is very high. With the use of air-conditioner, the temperature difference between the inside and outside of the building is very less. There is only a thin glass barrier to prevent the outside heat from coming in. This results in in excessive loss of energy. Due to convection, air circulates inside and acts as a barrier, preventing outside heat from coming inside and the cool air inside from escaping. This results in energy saving. Transparency: IGUS help in reducing the incidence of condensation on the warm air side and bring about transparency. They can be used in larger glazed areas without increasing energy consumption while ensuring transparency. For example, insulated glass is used in soft drink chillers in retail stores, airports, etc. Reduced Infiltration In cold climates, the aim is to reduce infiltration of the cold, maintain internal heated temperature and reduce the cost of heating. IGUs help in achieving these objectives. Reduced Condensation: Water from condensation and the resultant water run-off can damage window sills and frames, and seep into walls and adjoining areas. Window surfaces being colder than other surfaces in the building are more prone to condensation build up. An IGU reduces the likelihood of condensation by providing a thermal barrier between the inside and the outside. Acoustic Insulation Monolithic glass resonates when high frequency sound comes in because it cannot withstand the high frequency. IGUs are highly effective in reducing sound transmission. Air inside the IG will prevent the resonance from passing through. For example, buildings near airports, railway stations, and main roads are constructed using IG to prevent noise from entering the building. Applications: Sloped/Overhead Glazing Curtain Walls Storefronts Xtreme Non-vision (Spandrel) Locations Commercial/Residential Fixed and Operable windows Have a Query? Get in touch

Windows are to the house; what fresh air is to us. Just like us, our house too needs to breathe; to inhale freshness and exhale staleness. Windows bring in the much-needed light and air, besides allowing the outdoors in. They showcase the outside world and break the monotony of everyday life. THE 3-O APPROACH Windows have a three-pronged or what we call The 3-O Approach - Objective, Orientation and Overall Look. Objective Windows are beyond mere aesthetics.They Enhance the visual appeal of the house Let in daylight Offer convenience like letting out hot air and enable cross-ventilation Provide energy efficiency, thus reducing power costs. Provide sound insulation from external noise Ensure Safety from both man-made and natural hazards Connect us to the outside world Orientation Not for nothing, are windows designed with a sense of direction. South facing windows will have more sunlight through the day East & West facing windows will get morning and evening sunlight Factor in the direction of the breeze Xtreme Check surrounding buildings and outdoor views to identify the right orientation of the windows Overall Look: Base the overall look on the architectural design. For example: Traditional Kerala Home Comprises a long, sloping roof to safeguard the home’s walls and cope with the heavy monsoon rains Displays pillars on walls erected on an elevated plinth, to protect against dampness Windows: Casement windows on all floors provide both ventilation and views Modern Kerala Home Showcases a sturdy horizontal design with spacious open floor plans, deliberate asymmetry, and large glass windows or glass walls Features more glass everywhere –large windows, balustrades and doors Windows: Large-sized windows, Fixed and sliding types COMPONENTS OF WINDOW 1. FRAMES Once the type of window is selected, selecting the frame is the next step to provide durability to the window and ensure its longevity. A. Frame Build:Good quality uPVC windows offer benefits like premium look, thermal comfort, low maintenance, noise reduction and durability B. Frame Colour: uPVC frames come in colours & textures to enhance the aesthetics of interiors.The frames can be white-that-stays-white Frame, textured frames and vibrant-coloured frames 2. GLASS Over 90% area of the window is its glass. The type of glass used has an impact on: The amount of light coming through the window The flow of heat in and out of the home The amount of external noise The energy-efficiency A. Types of Glass: Clear Glass - Simple glass that keeps the world outside from the inside Tinted Glass - Enhances the aesthetics of the home Sunban-Ideal for windows in Indian climatic conditions, specially engineered to maximize light and minimize heat; optimises daylighting, cuts UV radiation and up to 70% solar heat and offers superior insulation. B. Glass Fitment: Every glass comes with a specific fitment into the window, as a Single Glazed Unit (SGU), Double Glazed Unit (DGU), or Laminated. Components of Laminated Glass SINGLE GLAZED DOUBLE GLAZED LAMINATED A single layer of glass that provides medium to low energy-efficiency, depending on the glass chosen. Providing higher energy efficiency, a Double Glazed Unit comprises two panes of glass (an interior glass pane and an exterior one) and an embedded layer of inert gas which creates an insulated environment between the interior and exterior of a window. Comprising two or more layers of glass sandwiched with a polymeric interlayer like Polyvinyl butyral (PVB), Laminated Glass provides safety and acoustic comfort. 3. Hardware Good hardware is designed to enhance the look and style of the windows while ensuring smooth, effortless operation, for years to come HARDWARE IN A WINDOW: Comprises handles, hinges and locks Enables ease of operations & ergonomics Adds to the aesthetics TYPES OF WINDOWS Windows typically belong to one of the following types: Sliding Windows Shutters that glide either way to both the left and right, in one frame Casement Windows Shutters open both ways, as per window type Fixed Windows Non-openable and fixed on all sides Awning Windows Hinged at the top, and open outwards Tilt And Turn Windows Non-openable and fixed on all sides Bay Windows Collection of three or more windows angled towards each other Combination Windows Combination of sliding, casement, fixed, awning or tilt-and-turn windows Get in touch

Processed Glass is that which is subjected to different types of treatment to make it suitable for diverse applications. Annealed Glass Annealed Glass is unprocessed glass or glass which has not been subjected to any treatment – for instance, toughening, lamination or heat strengthening. Commonly known as 'normal' glass, it is typically used for residential windows. Annealed Glass has minimal residual stress, with the stress being uniformly distributed. With a sudden change in temperature, the glass can break into very sharp fragments. Because of its low levels of toughness, tensile strength and thermal shock resistance, the use of Annealed Glass is not very prevalent. Tempered Glass Tempered Glass is glass that is processed by treatment – either thermal or chemical. It is also known as Safety Glass because it is known to be four times stronger than regular annealed glass. Unlike normal glass, it shatters into small fragments when it breaks, thereby lowering the risk of injury. Tempered Glass has much higher tensile or bending strength as well as better thermal shock resistance, with the ability to withstand temperature changes of up to 200 Degree Celsius without breaking. Tempering Process In the Tempering Process, stress is developed in the glass in order to increase its mechanical strength up to 4 times that of annealed glass. The stress is so created to bring the outer surface under compression and the core under tension. When the outer surface is under compression, the glass gets its strength; when the core is under tension, in the event of a breakage, the glass breaks into small pieces. There are two types of Tempering: Thermal Toughening and Chemical Toughening. Heat Strengthening The process of Heat Strengthening is similar to toughening, but in this, cooling is done in a slower manner. Heat Strengthened Glass is that which has been subjected to heat in order to increase Mechanical Strength and Resistance to Thermal Breakage (The process increases resistance to mechanical and thermal stress up to 130 Degree Celsius). The glass is twice as strong as annealed glass; however, its fragmentation pattern is also much the same. Tempering vs Heat Strengthening Heat Strengthened Glass is cooled down with lesser pressure. The key lies in creating sufficient stress level. Applications of Heat Strengthened Glass Though not suitable for safety glazing applications, Heat Strengthened Glass is ideal where optical requirement is high. It is used in high wind load areas, and general glazing where additional strength and/or resistance to mechanical and/or thermal strength are desired. It is popularly used in laminated glass for additional strength (overhead or sloped glazing). Lamination Laminated glass comprises two pieces of glass with a PVB interlayer. In the event of a breakage, this interlayer holds the glass in place so that shards of glass are not strewn around and cause injury. Benefits of Lamination Safety, Resistant to bullets, blasts and cyclones, Acoustic control and Privacy Components of Laminated Glass 01 Outer Lite A single layer of glass that provides medium to low energy-efficiency, depending on the glass chosen. 02 Inter Layer Providing higher energy efficiency, a Double Glazed Unit comprises two panes of glass (an interior glass pane and an exterior one) and an embedded layer of inert gas which creates an insulated environment between the interior and exterior of a window. 03 Inner Lite The Inner Lite can be tempered, heat strengthened or annealed. The thickness could range from 2mm to 19mm. Heat Soak Test Glass is heated to 290 +/- 10 Degree Celsius with a testing time for 2 hours. This test is used to to reduce the possibility of spontaneous glass breakage which can occur in tempered glass due to the presence of activated Nickel Sulphide. Although Nickel Sulphide is present in glass as part of the glass composition, it can get activated only during the process of tempering. The Heat Soak Test conforms to EN14179. Have a Query? Get in touch

Dictionary of most important terms used in Glass Industry Annealed Glass Glass that does not undergo the process of toughening, lamination or heat strengthening. Also known as 'normal' glass and most commonly used for flat glass. Balustrade A barrier or form of guarding, generally waist-high, which protects people from falling where there is a change in floor level, for example stairs and balconies. Bead A strip of wood, metal or other suitable material attached to the glazing surround to retain the glass. Body-Tinted Glass Transparent float glass with a consistent colour throughout its depth. Bolted Glass Assemblies / Assembly Systems Structural bolted glazing systems incorporating fixed or articulated bolts. Bow A form of distortion in toughened and heat strengthened glass, inherent to the manufacturing process. Bullet-Resistant Glazing Security glazing affording a defined resistance against the firing of specified weapons and ammunition Blown Glass The shaping of glass by blowing air through a hollow rod into the center of a molten glass gather. Curtain Walling Non-load bearing, typically aluminium, façade cladding system, forming an integral part of a building's envelope. Cast Glass Glass produced by 'casting', by pouring molten glass into a mould or by heating glass already contained in the mould until the glass melts and assumes the shape of the mould. Cut Glass Glass that is decorated by using grinding stones that are worked wet to cut designs onto the glass. Clear Glass Transparent glass with an almost colourless and neutral appearance. Daylighting The reorientation of daylight by means of systems incorporating reflective and adjustable surfaces or grilles. Daylighting systems redirect natural light, distributing diffused light in a room space and prevent strong areas of glare. Double Glazing Double glass panes divided by an inert gas space, the objective being thermal/acoustic insulation. Energy Balance The difference between the amount of heat gain and heat loss through glazing. Also known as the "Effective U-Value". Emissivity Emissivity is a surface characteristic of a material. It is the relative ability of a surface to absorb and emit energy in the form of radiation. Low-emissivity (Low E) coatings reduce the surface emissivity of the glass. The coatings are mainly transparent over the visible wave. Energy Absorptance (A) The percentage of solar radiant heat energy absorbed and re-emitted externally and internally by the glass. Energy Reflectance (RE) The percentage of solar radiant heat energy reflected by glazing. U-Value The heat transfer coefficient because of temperature differential between outdoor and indoor. Expressed in terms of watts of energy transfer per square meter per degree Celsius or degree Kelvin. Energy Transmittance (T) Percentage of solar energy flow transmitted directly through the glass. Enameled Glass Opaque glass colors, which are actually glass powders, that are melted onto a glass surface.. Facade Face of the building. Fenestration Any area within the building, that lets in light. Includes windows, glass doors, glass block walls and skylights. Fibre Glass Very fine strands of glass used in the form of glass wool. Flat Glass A commonly used terminology to indicate sheet glass, float glass and other forms of rolled/plate glass where the shape of the glass is flat. Float Glass Produced when molten glass is floated on a bath of molted tin to form a continuous glass ribbon. Also a type of flat glass. Frit Ground glass, ranging in a variety of sizes from fine powder to gravel-like size. Sometimes used for painting effects and can be fused or cast. Glazing Materials The materials required for the glazing of glass products such as glazing compounds, tapes, sealants and gaskets. Glazing The process of securing glass into provisions made in buildings, especially doors, windows and partitions. G-Value (g) Abbreviation or symbol for Solar Factor according to EN 410, formerly abbreviated to SF or TT. Gather A ball of molten glass taken from a pot or furnace on the end of a hollow blow rod. Glass Colourless, tinted, transparent or opaque, an inorganic product of fusion cooled without crystallizing. Referred by the name 'monolithic glass'. Hard and brittle with a conchoidal fracture. Heat-Strengthened Glass Glass which has been heat-treated in order to increase its mechanical strength and resistance to thermal breakage. It has fracture characteristics similar to that of ordinary annealed glass and is not classed as a safety glass to BS 6206. Heat-Treated / Heat Treatment A generic term for glass that has been heat-strengthened or thermally toughened in order to increase its mechanical strength and resistance to thermal breakage. Insulating Glass Unit (IGU) An assembly comprising at least two panes of glass, separated by one or more spaces, hermetically sealed along the periphery. Kiln Insulated chamber for heating and cooling glass or ceramics. Kiln-formed Glass that is altered, fused, shaped, slumped, or textured by the heat of a kiln. Laminated Glass / Laminate / Laminating Two or more sheets of annealed or heat treated glass are separated by one or more plastic interlayers (normally PVB) and subjected to heat and pressure, in order to ensure perfect adhesion between constituent elements. Light Reflectance (LRe) The proportion of the visible spectrum that is reflected by the glass. Light Transmittance (LT) The proportion of the visible spectrum that is transmitted through the glass. Low Iron Referring to extra clear glass, which has a reduced iron oxide content in order to lessen the green tinge inherent to ordinary clear float glass. LSG Ratio Light to Solar Gain (LSG) is the ratio of the Visible Light Transmittance (VLT) and Solar Heat Gain Coefficient (SHGC) of a glass. In absolute percentage terms, a ratio greater than 1 signifies that the daylight passing through the glass is more than the sun’s direct heat passing through it. Lacquered Glass Produced by depositing and baking lacquer coating on one side of clear glass. Low Emissivity or low-E Glass Glass with a special thin-film metallic or oxide coating which allows the passage of short-wave solar energy into a building but prevents long-wave energy produced by heating systems and lighting from escaping outside. Allows light to enter while also providing thermal insulation. Monolithic Glass A single sheet of flat glass that could be annealed/toughened/heat strengthened. Mirror Polished glass with a reflective coating of silver deposited on the back. Maximum Thickness The thickness of a glass pane at the maximum thickness tolerance. Minimum Thickness The thickness of a glass pane at the minimum thickness tolerance. Nominal Thickness Numeric designation to indicate the approximate thickness of glass. Outdoor light reflectance (%): Outdoor light reflectance, or daylight reflectance, is the percentage of light striking the glazing that is reflected back. It indicates the degree to which the glazing appears like a mirror from the outside. Outdoor light reflectance (%): Outdoor light reflectance, or daylight reflectance, is the percentage of light striking the glazing that is reflected back. It indicates the degree to which the glazing appears like a mirror from the outside. Outdoor light reflectance (%): Outdoor light reflectance, or daylight reflectance, is the percentage of light striking the glazing that is reflected back. It indicates the degree to which the glazing appears like a mirror from the outside. Outdoor light reflectance (%): Outdoor light reflectance, or daylight reflectance, is the percentage of light striking the glazing that is reflected back. It indicates the degree to which the glazing appears like a mirror from the outside. Pyrolytic Coating / Coated A specialist metallic coating is applied to the glass "online" during the float glass manufacturing process. The high temperatures involved resulting the metallic oxides fusing into the surface of the glass through pyrolysis and effectively forming part of the glass. See SGG Antelio Plus, SGG Reflectasol, SGG Bioclean. Pane A ready-to-be glazed single piece of glass or plastic glazing sheet material in a finished size. Patterned Glass Rolled Glass with patterns. Can be on either or both sides of the glass. Reflective Coating / Coated A metallic coating is applied to one side of the glass in order to significantly increase the amount of reflection by the glass of both the visible and infra-red (light and heat) range of the electromagnetic spectrum. Rolled Glass Translucent glass with 50-80% light transmission. Used where transparency of the glass sheet is not important or desired. Structural Glazing Glass acting as a structural support to other parts of the building structure, for example glass fins. It can also refer to glass that is fixed by means of bolted connectors where the glass is not acting as a structural element. Self-Cleaning / Self-Cleaning Glass Glass with a photocatalytic and hydrophilic coating. The coating harnesses the dual-action of UV light and rain (or water) to break down organic dirt and reduce the adherence of mineral material. The glass stays cleaner for longer and is easier to clean. Safety Glass Glass which must have passed an impact test (BS 6206:1981) and either must not break or must break safely. Safety Critical Locations Identified by BS 6262 part 4 and defined as glazed sections of a door, wall or other part of a building most likely to be subject to accidental human impact. Solar Heat Gain Solar radiant heat, transmitted or re-emitted by glazing into a building, contributing to the build-up of heat. Safety Glass Glass which does not disintegrate into sharp and potentially dangerous splinters when broken. May be produced by laminating or tempering. Sheet Glass A transparent flat glass with apparent glossy, fine finish but with waviness of surface. Skylight A fenestration surface that has a slope less than 60 degrees from the horizontal plane. Translucent Transmitting light but obscuring clear vision. Thermally Toughened Glass Glass that has been subjected to a controlled heating and cooling process, in order to significantly increase its resistance to mechanical and thermal stress. Through the thermal toughening process, the glass attains its safe-breakage characteristics. Transom A horizontal framing bar between glass panes. It can also be used to refer to a fanlight over a door. Thermally Insulating Glazing Double-glazed units provide thermal insulation. Transparent Clear, permitting vision. Tinted Glass A float glass to which colourants are added during manufacturing, resulting in tinting and solar radiation absorption properties. U-Value The heat transfer coefficient because of temperature differential between outdoor and indoor. Expressed in terms of watts of energy transfer per square meter per degree Celsius or degree Kelvin. Unframed Glazing Glazing with one or more edges unframed. Visible light transmittance (%): Visible transmittance, or daylight transmittance, is the percentage of visible light striking the glazing that will pass through. Visible transmittance values account for the eyes’ relative sensitivity to different wavelengths of light. Glazing with a high visible transmittance appears relatively clear and provides sufficient daylight and unaltered views; however, it tends to create glare. Glazing with low visible transmittance is best used in highly glare-sensitive conditions, but can create gloomy interiors under certain weather conditions and diminished views. It is unsuitable for many day-lighting applications since it does not provide enough light for typical visual tasks. While glazing can have a high visible transmittance, it does tend to obscure views, e.g., frosted or patterned glass. Vertical Fenestration Any type of fenestration other than skylights. Wired Glass Flat rolled glass reinforced with wire mesh and used especially for glass doors and roofing to prevent objects from smashing through the glass and also to hold pieces of broken glass together. Produced by continuously feeding wire mesh from a roller into the molten glass ribbon just before it undergoes cooling. Protects against break-in and fire spreading. Have a Query? Get in touch