If you’ve ever had the windows of your home or office tinted or replaced, you’ve probably been asked or informed as to whether your windows are “Low-E.” This article will provide a brief description of what Low-E windows are, how they work, and how they may affect your choices in window tint.
The phrase “Low-E” stands for “low emissivity,” meaning there is low emission of UV and infrared energy that passes through the glass. Low emissivity glass has microscopic layers of metallic oxide that reflect energy waves that would otherwise pass through your glass into the space of your building. This energy measures as either infrared (heat-generating) waves or as Ultraviolet waves, which contain damaging energies from the sun. Low-Eglass minimizes the energy transfer from your building’s outdoor environment to the inside which may ultimately help with energy costs as well as damage repair caused by ultraviolet rays.
Window tint is another effective way to combat the sun’s energy to save energy costs and prevent ultraviolet damage. However, installing low emissivity interior window tint on top of Low-E windows often does not result in still-lower energy transmission since most of the energy is reflected from within the glass before the window tint has a chance to do its job. One way to combat this is by installing an exterior tint film which would then allow the film to perform before meeting the metallic oxide of the Low-E window.
Does this window still need tint if I already have low-E glass? That is ultimately up to the customer, because there is a wide variety of window films whose purpose goes beyond that of energy emissivity. For example, low-E windows may still provide a lot of glare or light to pass through that the customer wants to get rid of. If that’s the case, a low visible light transmission (VLT) window film may help with their glare problems.