Low-E coatings have been around since the 1980's, although the term remains generic and in dire need of explanation. While the standard for window installation today, many older buildings and homes could benefit from window replacement in order to better protect not only the inhabitants, but also the furnishings.
The Basics of Low-E Coatings
Low-E coated windows were originally invented to retain infrared light and trap warm temperatures inside the room, a feature that made them very cost-effective in colder climates. The windows themselves would remain warm which also aided in reducing levels of condensation.
Today, Low-E coatings can help with a larger number of issues, including the opposite—keeping a room cooler than the outside during hot summer days. Low-E—or low emissivity—coatings are meant to act the part of a sieve. Short wavelengths can make their way through, allowing visible light inside, while long wavelengths, the ones that carry heat, are kept at bay.
Coated windows are not to be mistaken for tinted glass, where alloying materials are added into the glass and efficiency is directly proportional to thickness. In the case of Low-E coatings, the metallic particles are applied to the glass in one or more layers.
Low-E Coating Versatility
The coating can be applied to all types of glass, including the double hung window. Soft coats are more reflective and better energy savers but they have to be applied to the interior surface. Hard coats, while not as good, go on the exterior surface and can withstand the elements without issues.
Together with a windows installer, you can assess what types of coating will work best for you. The layers can contain an array of materials, some better for low UV values, others better suited for protection from fading. Combined with tinting agents and argon gas, your windows can turn into highly efficient insulation.
Does overall cost justify window replacement? The answer is a resounding yes. Due to low-E coating, windows can contribute substantially to lowering utility bills.
By acting as an insulator, windows keep heat inside during the colder months of the year, so the central heating system doesn't have to work as hard. In summer, low-E coated windows keep rooms cooler, taking a load off the AC unit. Low-E coatings can also prevent damage to furniture and carpets by keeping harmful UV rays at bay.