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If you have ever shopped around for new windows or doors, you know that these products carry energy performance ratings. Unfortunately, few people really know how to read these labels. So while they are meant to help you compare products, in most cases they are just more confusing than anything else. Because windows and doors are such a large investment, you want to know exactly what you are purchasing. So here is some information to help you decode the labels on your windows and doors.

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Which Labels Matter?

There are two labels you will want to inspect. They include the Energy Star label and the National Fenestration Rating Council label. The NFRC is an impartial third party that voluntarily tests products to provide fair and accurate ratings. It provides raw numbers on the product’s performance. The Energy Star label will tell you whether or not those numbers showcase a high level of performance for your region, and specify the climate zones for which those products are best suited.

Understanding the Energy Star Label

Here, the information is pretty straightforward and where you live impacts which measurements are most important. This label tells you if the ratings on the NFRC meet the standards for your region. So in northern regions with colder winters and milder summers, you want windows with a higher Solar Heat Gain Coefficient (SHGC) and lower U-factor. That helps naturally warm your home with sunlight and trap heat inside.

Understanding the NFRC Label

Here are the ratings you will see and what they mean:

1. U-factor

This rating indicates how well the window blocks heat transfer from the inside to the outside. This is especially important in winter when you don’t want heat escaping. No product will trap heat completely and generally the numbers fall between 0.1 and 0.6. The closer the number gets to zero, the better it is at insulating.

2. Solar Heat Gain Coefficient (SHGC)

This measurement indicates how well windows and doors resist heat gain from the sun. Here in the NY metro area, where we have the heat on most months of the year, solar heat gain helps to supplement the work of our heating systems. In the southern US where AC rules, it is more important to block unwanted solar heat gain. SHGC ratings range between 0 to 1, where a lower number indicates more resistance and a higher number indicates more transfer.

3. Visible Transmittance

While it doesn’t have anything to do with energy efficiency, this rating conveys how well your windows and doors allow natural daylight into your home – the main reason we have windows in the first place. The measures taken to affect U-factor and SHGC have an impact on the ability of the glass to transmit light, so you want to find a balance between performance and daylight. VT ratings range from 0 to 1. To maximize natural light, choose a window with a high VT rating.

Talk to a Professional Today

Ultimately, talking to a window professional is the best way to determine which ratings are best for your home. Call the experts at Home Supply Window and Door at 973-949-5401 or stop by 160 Van Winkle Ave, Hawthorne, NJ 07506.