Low-E stands for low emissivity, or low thermal emissivity and is a surface treatment on the glass that lowers the levels of radiant thermal energy (Infrared “IR” light) and ultraviolet “UV” light.
Simply taken from Wikipedia, this coating helps “keep heat on the side of the glass where it originated, while letting visible light pass. This results in glazing with better control of energy – heat originating from indoors in winter remains inside (the warm side), while heat during summer does not emit from the exterior, keeping it cooler inside.”
The addition of Low-E glass becomes very important when considering a well insulated home. With single glazed or aluminium frame windows, any heat that is allowed to enter the home in the form of sunlight is also allowed to exit the home through that same window due to that window’s low thermal performance.
However, any well insulated room (or home) will require less energy to heat or cool it. The insulated room better retains any heat that is already there. If we kept adding the same amount of heat by using clear glass from the poorer performing windows, then this leads to too much heat accumulating in the room. This can result in an uncomfortable or unhealthy overheated situation.
Please feel free to contact us for more information.