How to Determine if Your House Needs More Insulation

Use a handheld infrared thermometer, available at home improvement stores, to take the temperature of the outside air. You'll actually be taking the temperature of objects that are outside, according to the North Dakota State University Cooperative Extension. For example, take readings of porch chairs or garden stones by holding the thermometer up to the items. All of the items should measure the same as the outdoor air.

Take the temperature of both the interior and exterior walls in an insulated room in your home, using your infrared thermometer. An interior wall is a wall in the room that backs against another room in the house while an exterior wall is a wall that provides a barrier between your house and the outdoors. An infrared thermometer gives you the most accurate reading of the ambient temperature when you hold it within 1 to 3 feet of the wall you're measuring. If the temperature reading of the two walls differs by more than just a couple of degrees Fahrenheit, you probably could use more insulation in your home.

Measure the thickness of existing insulation in your attic, basement or crawlspace. Use a regular tape measure to identify the thickness, in inches, of the existing insulation.

Identify the R-value of the insulation in your home. According to the U.S. Department of Energy, R-value stands for resistance to heat flow. Determine the R-value with the measurements taken and some simple math. If you've got pink, white or yellow fiberglass insulation, multiply your depth in inches by 2.5 for loose fibers or 3.2 for batts, or precut rolls. If you have gray, white or black-specked rock wool insulation, the R-value is your depth multiplied by 2.8. The results of your math is your R-value.

Check what the recommended R-value is for the area in which you live. Energy Star, an agency of the U.S. Departments of Energy and the Environmental Protection Agency, lists recommended R-values according to climate zones on its website. Compare your recommended R-value with the actual R-value you find in your home to determine if your house needs more insulation.