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How To Identify The Most Efficient Replacement Windows


Boulder, CO replacement windows

Shopping around for replacement windows can be daunting. After you look at one window and then another, you might start to get confused. They all look the same, right? How can you find one that is more efficient and will meet your home’s needs? replacement windows all fit into one standard and a certain ratings system that can really help you gain access to the most efficient replacement windows on the market today. All you have to do is understand it.

The National Fenestration Rating Council, or NFRC has come up with a measurement system that helps you identify energy efficiency in windows. This system is overseen by the non-profit, independent organization so you know no one is making money off putting certain labels on certain windows. They look into replacement windows as well as doors and even skylights. The single measurement system helps you compare various windows so you’re looking at apples to apples when you read the labels. Now, all you have to do is learn how to read the labels and you’re set up to find the most energy efficient replacement windows for your home.

Label Reading Starts With U-Factors

The U-factor is one of the first numbers you will notice on replacement window labels because it’s a very important rating to understand. The measurement indicates how much heat flows through a window. The U-factor will be lower if the window is efficient. The reading includes the glass, the frame, and the sashes on the window and any of those things can have an impact. Two windows with the same glass, but different frame material will have varied U-factors. Two windows with the same frame, but different glass packs will also vary. Many homeowners like to start by looking at windows with the Energy Star label on them, since they know they meet certain requirements, and then compare the U-factors from there.

Continue With The R-Value

The R-value will show you how capable a window is at resisting heat flow through the glass. If the R-value is high, the glass will insulate the home better. This rating only takes the glass into account and not the rest of the window. A window with a high R-value and a low U-factor will not be the most efficient. If heat can’t get through the window’s glass, it could still leak through the frame or sashes.

Higher R-Value = Better insulating Glass Package

Lower U-Value = Better insulating Glass/Frame/Sash Combination

Keep SHGC In Mind

The Solar Heat Gain Coefficient measures how well replacement windows block the heat form the sun. Of course you want sunlight to come into your home for natural lighting. It feels good and can accentuate a space like nothing else. However, if the sun is too bright, it can also heat things up and cause your air conditioning to run harder and faster. The better SHGC glass packages can give you light without heat.

If you want to learn more about replacement window ratings and terms, contact Z Double B, Inc. at (303) 997-8168 or stop by 12860 W Cedar Dr #110B, Lakewood, CO 80228.

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