5 Questions Answered about Energy Efficient Windows

What makes a window more energy efficient than other types of windows? And what do these strange terms like “e-coating” and “u-factor” mean? We have answers to the questions most commonly asked about energy efficient windows!

1. What Type of Frame is Best for Energy Efficient Windows?

In the Northeast, winters are harsh and summers are hot — and moisture is an issue year-round. This means you’ll want to choose a window frame material to suit. Fiberglass comes as the most highly recommended choice because it stands up well to moisture and it also has low thermal conductivity. In other words, less heat is transferred through solid fiberglass or clad fiberglass frames.

2. Does Window Glaze Matter?

In a word: yes! Window glaze is a term that refers to the actual glass. Double glazed windows are the current standard (in other words, windows with two layers of glass, not one). Triple glazed windows, with three layers, are just starting to become more popular. Each layer of glass helps to reduce thermal transfer and what’s more, the insulating materials between the layers of glass, like argon gas, glass coatings and films, all add insulating properties of their own. The most energy efficient windows will feature double or triple panes and a combination of argon and specialized coatings to help insulate against thermal transfer and the sun’s rays.

3. What is an E-Coating?

Low-E windows first hit the market in the 1980s and although they’re not often talked about, an e-coating is important for energy efficiency. At the outset, low-e windows had a coating that essentially helped to heat homes in cold regions of the United States by allowing UV rays through the glass and then reflecting them back into the room, creating a sort of greenhouse effect. In the summer, however, this proved problematic as people sought to cool their homes. Modern low-e windows solved this problem with low-e windows that not only help hold heat in the winter but reflect certain types of light during the hottest months of the year. Low-e windows are a great way to regulate heating and cooling costs all year round.

4. What Does the U-Factor Mean?

The u-factor is to windows what the r-value is to insulation. Windows with lower u-factors are overall better at reducing the flow of heat into and out of the home. This is all based on a variety of things, including the glazing, the frame choice, window coatings and more. To choose energy efficient windows, choose windows with the lowest possible u-factor.

5. Sliding Versus Swinging: Which is Better?

Drafty windows are an all too common problem but choosing the right style of window can help you eliminate drafts. If you’re looking to reduce drafts, think about window styles that swing open — awnings and casements, for example. These windows seal by pressing against the weather stripping when shut. As long as the weather stripping is intact and the window is tightly closed, there should be no draft. Sliding windows, on the other hand, tend to be draftier because it is impossible to completely seal the sliding mechanisms without jamming the window shut permanently.

Energy efficient windows are essential to lowering heating and cooling bills, particularly in the extreme heat and cold of the Northeast! Let these questions be your guide to choosing windows for your home.