Reviewed and Revised on 10/10/2013
A simple way homeowners can check their homes for heat loss is with an infrared thermometer. Infrared thermometers vary in cost, but generally are around $50. Depending on the season, a homeowner can find areas in a home where air and heat are leaking. The bigger the difference between the inside and outside temperature the easier it is to detect heat leaks. The North Dakota State University Extension service has developed a publication Determining Insulation and Air Infiltration Levels Using an Infrared Thermometer that describes the process of evaluating your home for heat leaks.
Infrared images showing heat leaking through garage door, a crack in basement foundation, and missing insulation above a window
Professional auditors use an infrared camera. An infrared camera translates radiation into a visual image. An auditor will use this image to see where heat is leaking into or out of a home. When used with a blower door, the leaks are accentuated. There are a wide variety of infrared cameras. Cost can range from anywhere from $1000 to $50000, depending upon features.