Glass Size, How to calculate glass size
Glass size speaks to how to calculate glass size and how to determine glass sizefor building construction.
It is determined in the manufacturing process where it is produced in a series of sizes ranging from 3/32 inch (2.5 mm) to 1/8 inch ( (3 mm) and this is known as single strength. When manufactured up to as much as 1 inch (25.4 mm) it is referred to as double strength. The varied sizes are dependent on manufacturer choices.
Glass thickness for a particular window is determined by the size of the light and the expected maximum wind loads on the glass. For low buildings with relatively small windows, glass 1/8 inch thick is usually sufficient. For larger buildings and for windows in tall buildings, where wind velocities are high at higher altitudes, thicker glass is generally required, along with increased attention to how the glass is supported in its frame.
It has become standard practice for architects and structural engineers to order extensive wind tunnel testing of models of tall buildings during the design process to establish the expected maximum wind pressures and suctions on the windows.
Because of unavoidable manufacturing defects in the glass, as well as the probability of damage to the glass during installation and while it is in service, a certain amount of breakage must be anticipated in a large building.
Building code ASTM E1300 establishes standard procedures for evaluating the structural stability and probability of breakage for a window of given dimensions, support conditions and wind pressure.
During its manufacture ordinary window glass is annealed, meaning that it is cooled slowly under controlled conditions to avoid locked in thermal stresses that might cause it to behave unpredictably in use. Other types of glass have come into use for particular purposes in buildings.
Glass Production (Wikipedia)
Following the glass batch preparation and mixing, the raw materials are transported to the furnace. Soda lime glass for mass production is melted in gas fired units. Smaller scale furnaces for specialty glasses include electric melters, pot furnaces, and day tanks.
After melting, homogenization and refining (removal of bubbles), the glass is formed. Flat glass for windows and similar applications is formed by the float glass process, developed between 1953 and 1957 by Sir Alastair Pilkington and Kenneth Bickerstaff of the UK's Pilkington Brothers, who created a continuous ribbon of glass using a molten tin bath on which the molten glass flows unhindered under the influence of gravity.
The top surface of the glass is subjected to nitrogen under pressure to obtain a polished finish. Container glass for common bottles and jars is formed by blowing and pressing methods.
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