Reflective coated glass speaks to what is reflective coated glass and why use reflective coated glass.
This glass is used to help with deal with building solar heat gain. Solar heat buildup can be a problem in buildings with large areas of glass, especially during the warm part of the year. Fixed sun shading devices outside the windows are the best ways of blocking unwanted sunlight, but glass manufacturers have also developed glasses that reduce glare and cut down on solar heat gain.
The transparency of glass to visible light is called its visible light transmittance. It is measured as the ratio of visible light that passes through the glass relative to the amount of light striking the glass. Clear glasses have visible light transmittance in the range of 0.80 to 0.90, meaning that 80 to 90 percent of the visible striking the glass passes through to the building interior. The remaining 10 to 20 percent is either reflected or absorbed by the glass and converted to heat.
Thin durable films of metal or metal oxide can be deposited on a surface of either clear or tinted glass sheets under closely controlled conditions to make reflective glass also called solar control glass. Depending on its composition, the film may be applied to the interior or exterior of the glass.
In double glazing, it may also be applied to either of the surfaces that face the space between the layers of glass. While remaining thin enough to see through, the film reflects a substantial portion of the incident visible light. Visible light transmittance and solar heat gain coefficients (SHGC) for reflective glasses vary significantly, depending on the density of the metallic coating and the tinting of the glass to which it is applied.
Reflective glasses appear as mirrors from the outside on a bright day and are often chosen by architects for this property alone. At night, with lights on inside the building, they appears as dark but transparent glass.
The sunlight reflected by a building glazed with reflective glass can be be helpful in some circumstances by lighting an otherwise dark urban street space. It can also create problems in other situations by bouncing solar heat and glare into neighbouring buildings and onto the street.
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