How to Compare Heat Loss Through Glass vs. the Frame of a Vinyl Window

A more efficient window can save you money.

When you are shopping for new windows for your home, you need to keep in mind what a huge investment this is. It's an investment of both time and money, so you need to pay attention to all of the ratings and the efficiency level of the glass for the windows, as well as the frame, such as a vinyl-framed window. The amount of heat loss for the window is measured in a few different ways, and all of the information you need to compare your options can be found right on the product label.

Instructions

1. Find the product description for the glass and vinyl window frames that you're comparing. No matter what type of window you're comparing, the product label will contain some efficiency ratings that relate to heat loss.

2. Look at the R-value for each window you're comparing. The R-value lets you know how resistant the window is to losing heat when the weather gets cold. If you want a more efficient window, then choose one with the highest R-value.

3. Check out the U-factor. This is actually the thermal transmission for the windows you're comparing, meaning the U-factor measures heat transfer through the window. Unlike the R-value, the U-factor should be the lowest number possible.

4. Find out if the glass on the windows contains a low-emissivity coating, which is also called a low-e coating. This coating helps improve the overall efficiency of the window and reduces heat loss when the weather gets cold.

References

• National Fenestration Rating Council; The Facts About Windows & Heat Loss; January 2005