How Do You Measure Energy Efficiency of a Window?


If you would like to replace your windows and doors, you need to consider their energy efficiency before choosing any products. However, understanding the energy efficiency of a window can be quite convincing in many instances. This is why you need to know how to measure the energy efficiency of a window.

Here, we will explain the various things you need to know about measuring the energy efficiency of a window.

What do you need to measure?

For the energy efficiency of a window, the main things you must measure include:

  • U-value and R-value

U-value determines the ability of a window to transmit heat. An energy-efficient window has a lower U-value. Similarly, you also need to measure the R-value, which is the measurement of the ability of a window to resist heat flow. Unlike U-value, R-value must be higher for an energy-efficient window.

  • Solar heat gain coefficient (SHGC)

This is for measuring the ability of a window to lower heat gain. It relies on how a window can block rays from coming into a building. It is represented by a number between 0 and 1.

A window with higher SHGC will enable lots of heat and sunlight to come into the building. This can make life difficult for you during the summer when everywhere is hot. Therefore, you should consider going for a window with lower SHGC.

  • Air leakage

This refers to the amount of air that comes into a building due to the cracks or other kinds of openings in it. The lower the air leakage, the higher the energy efficiency of the window.

Ways for determining the energy efficiency of a window

If you want to measure the energy efficiency of a window, you should do the following.

  • Measure with an infrared laser thermometer

With a single push of a button, you can use an infrared laser thermometer to determine whether a window is energy efficient or not. Use this tool to measure the temperature close to your windows as well as an interior portion of your house. Compare the two measurements to determine if your window is efficient or not.

  • U-value kit

The U-value kit is a high-tech tool that can be utilized for determining the effectiveness of a material as an insulator. You need to put the sensors of the kit on both the exteriors and interiors of the windows you want to measure. Then, connect the data logger of the kit and the sensors. Afterward, connect the data logger to your computer to get the right measurements for the energy efficiency of your windows.

You can also use the instruction on the kit to learn how to use this tool.

However, if you cannot afford any of these high-tech tools for determining the energy efficiency of your windows, you can consider a visual inspection or a smoke test.

With this set of information, you should be able to measure the energy efficiency of your windows and doors. The measurements will play a key role in helping you to decide whether you need to replace your windows or not.

Jeffrey Morgan

The author Jeffrey Morgan