Who Cares about Emissivity?

The emissivity of a material is one of those things that is used to describe how much heat the surface emits. So, it stands to reason that a low-emissivity (Low-E) product emits relatively low energy. The reason that Low-E coatings on window glass are so important is because they ensure that heat energy doesn’t have the ability to transfer between panes of glass. Here’s the problem: Let’s say you have a dual pane window that for whatever reason is not designed for energy efficiency. Direct heat from the sun naturally causes the outer pane of the window to warm up over the course of the day. This heat will then naturally transfer from the outer pane to the inner pane of the window, which causes the home’s interior to warm up over time. It’s one of the reasons that windows are among the most common places for costly heat transfer to occur in homes. To help prevent this natural heat emissivity, windows can be outfitted with a Low-E coating.

Since windows are naturally highly emissive, a special coating needs to be installed to improve their thermal efficiency. This coating is virtually invisible to the naked eye but is effective because it reflects the heat on the window glass. In other words, radiant heat:

• Bounces away from the home in the summer
• Is retained within the home in the winter

With that said, you’ll also want to make sure that you install energy efficient windows in your home that are optimized for your specific property because some heat gain can actually be beneficial. Here’s the thing about solar heat gain from the sun: In Northern climates, some natural heat can be harnessed to warm the house during long winters, which alleviates some of the burden on the home’s HVAC unit. So, while you certainly want replacement windows that are outfitted with energy efficient features, such as Low-E coating, it is also important that you work with a home remodeler who knows how to get the most out of your windows for your unique home. Something as seemingly trivial as the direction that the window faces can be unbelievably important.

To learn more about improving the energy efficiency of your home with the right kind of replacement windows, contact the experts at Alure Home Improvements.