Harmony Home Improvement

What Do NFRC Labels Tell You?

Roofs, siding, doors and windows – all these work together to provide homes and commercial spaces with sufficient insulation. If you are considering replacing any of them, especially your windows, you should make sure that you consider their energy-efficiency. One way to do that is to check the labels of the products you consider buying. Unfortunately, they can be quite confusing, however, Harmony Home Improvement’s expert window and residential and commercial roofing contractors are here to help you understand what they mean.

First of all, the National Fenestration Rating Council requires all their certified products to bear a temporary label, as well as a permanent one. These labels are proof that the products have met their standards.

These products include windows and skylights for both residential and commercial roofing systems. The temporary label, which is basically an adhesive sheet attached to the surface of the window has the product’s ratings for energy performance. The permanent label, which can either be on adhesive paper or etched does not show performance information but NFRC’s CPD (Certified Products Directory) number.

U-Factor and SHGC 

Simply put, U-factor determines a window’s heat loss performance. You should look for windows with lower values as those are the ones that can offer great insulation. You might want to consider double or triple pane windows that can have as low as 0.15 U-factor.

SHGC stands for solar heat gain coefficient, which is basically a figure that tells you how much solar radiation goes through a window or how much it can resist heat gain. The value is between 0 and 1 and you should choose products with a lower number if you want to avoid passive heating.

Both U-factor and SHGC values tell you how well the window can help keep your home from overheating during summer and keep your energy bills from shooting through the roof. Even in a commercial space, insulation is very important and the best ways to ensure sufficient insulation are through TPO roofing installation and getting the most energy-efficient windows.

Visible Transmittance, Air Leakage and Condensation Resistance

The other categories in an NFRC label are for Visible Transmittance, Air Leakage and Condensation Resistance. Visible Transmittance lets you know how well a window or skylight can let natural daylight in. This can help you determine whether or not a product can help you save some bucks on artificial lighting. In this category, the range is between 0 and 1, and you should go for a window with a higher number.
Air leakage, on the other hand, gives you an estimate of how much air (drafts) will possibly enter a room. The value can be anywhere between 0.1 and 0.3. A higher number means you’ll have to deal with more drafts so you should look for a low number.

Condensation resistance rating is not always included in an NFRC label, but if it is, a higher number is ideal. That means a product can resist condensation better.

Choosing windows and skylights should not just depend on the style of the products. As a home or business owner, you want to make sure that you are getting the most energy-efficient products, too.

If you have any questions about windows, siding, roofing and home improvement in general, don’t hesitate to give our pros at Harmony Home Improvement a call at (860) 516-9103 or fill out our online contact form for your next project. We serve Hartford, CT and the neighboring areas.


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