Seeing (Infra)red

The home inspector has many tools at his or her disposal to assist in providing the best possible inspection to our clients and none is more interesting (or fun) to use than the thermal camera. Simply put, it uses Infrared (IR) technology to superimpose a “heat signature” into a standard camera image. Here is a clear example of how it works: this is a picture of a portable air conditioning unit: it is obvious from this image it is a hot day! As a relatively new technology to our industry, there are a lot of benefits to using IR imaging, but it does have its limits:

IR Does Not Grant Superman Powers
While it certainly looks like X-ray vision, a thermal camera does not allow an inspector to see through walls. It can, however, identify cold spots, indicating poor insulation or potential moisture problems that warrant further investigation.

IR Works Based on Temperature Difference
While extreme temperatures are not pleasant (such as the hot day this blog post was written!) for an inspector they are a bonus on inspection day. Particularly in cold weather, it is easier to see the temperature difference between the outside and inside and therefore easier to determine if there are cold patches indicating poor insulation or an air leakage.

IR is Not as Simple as it Looks
In what seems to be a common theme to my writing, using a thermal camera looks simple but it more complicated than it appears. For example, the inspector needs to be aware that every surface has an emissivity rating (the ability of a surface to reflect infrared radiation), the angle of the image changes the apparent temperature, some materials (such as metals) give false readings and it is more important to look for qualitative data (temperature differences) than quantitative data (actual temperatures) when doing a thermal scan.

I am starting to sound like this technology has a lot of drawbacks but in reality, it is a fantastic piece of technology that usually provides valuable information for the inspector. Here are just some of the many useful ways I have used my IR camera both on the job and around the house:

• Finding evidence of an abandoned dryer vent in a garage
• Determining my child’s bath was dangerously hot
• Locating both the hot and cold water supply lines in a basement ceiling
• Ensuring the electrical system does not have any dangerous hotspots
• Checking air supply registers for appropriate airflow (or leaks)
• Finding my handprint on the wall after removing it because looks cool

The gallery below shows some visual examples of how useful IR technology can be for inspectors and homeowners alike. Like most of our tools, when used properly they can provide valuable diagnostic information invisible to the naked eye.