Window Replacement Rating Terms

Nov 12, 2018

Del Mar, CA window replacement

If you plan to invest in a Del Mar, CA window replacement project, the ratings on the windows you consider are very important. But most homeowners only get replacement windows once in their lifetime. How can you know what the ratings mean? It’s easy, but it does take a little time and effort to get to know the ratings system, so you can confidently compare what’s best for your family. Let’s take a look at the different ratings you’ll run across on window labels as you look for the right options.  

The U-Factor 

The U-factor is one of the most important ratings you’ll see on new windows. This number will tell you about the window’s resistance to heat flow. If you see a low number, that’s good, but the numbers range from 0 to 1. Windows with high insulation might have a .15 rating while a mid-range window will be somewhere more like .4. Keep the numbers low to save the most money and get the best window.  


The solar heat gain coefficient is a measurement that is also best when it is lower. It ranges from 0 to 1 as well and measures the solar radiation that comes into a home from the heat of the sun. Some windows absorb more heat than others and you want your windows to absorb the least amount possible.  


This rating won’t help you with efficiency as much, but it will show you how much light comes in through the window. If you want more natural light, choose a window closer to 1. IF you want some dimness, get something closer to 0. You can also get glazing, tinting, and other things to have an impact on this rating.  

Air Leakage 

This rating is easy to describe because it is as it sounds. The air leakage rating is the amount of air that moves through the window. Once again, lower ratings are better because you don’t want much air, if any, leaking through the windows and into your home.  

Comparing the numbers shows you why certain windows are more than others and what quality windows hold. You can also predict which windows will save you more money because of their insulating qualities. You want to stay within certain ranges and a good place to start is by finding windows with Energy Star labels on them, then go from there in comparing the specifics.  

Del Mar, CA window replacement project isn’t always simple and easy, but when you understand the basics of window ratings, you can compare and contrast the various windows yourself and make informed decisions. Of course, you can always ask for professional help as well by calling Window Solutions at (619) 258-0515. We’ll explain any of the ratings to you as many times as you want to hear it and we’ll ensure you have the information you need to make the best decision for your home. You can also visit us and look at labels in person at 11632 Riverside Dr Lakeside, CA 92040.  

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