Thermographic Inspections… Are they necessary?

Thermographic Inspections… Are they necessary?


The first thermographic cameras were extremely large, expensive awkward machines.

Over the years, the technology has improved, much reducing the size and prices of these amazing cameras.

Although still considered expensive as tools go, they are more affordable each year, so inspectors are beginning to add them to their arsenal of inspection equipment.

Throughout the article, I will also call them by their other common names, infrared thermal cameras, infrared imagers and thermographic cameras.

Essentially, infrared thermal cameras detect & measure temperature patterns on a given surface. The temperature differences are assigned colours for easy identification.

When combined with other tools, they can help identify a number of issues within a home. Although they are powerful and sensitive tools, they cannot see through walls, like Superman, or even through glass, as many people believe.

These cameras have gained recent popularity in the home inspection field due in large part to familiar TV programs, where they have been used to successfully find hidden defects. In addition to home inspectors, engineers, medical personnel, the military, contractors and a whole host of trade professionals are using these cameras with greater frequency.

Often the thermographic inspection will be an add-on service to a regular inspection. Thermography is not covered under the standards of practice we are governed by.

More and more clients are requesting that we (home inspectors) use them during our inspections; however, it is important to mention that they are neither appropriate nor effective for every inspection.

Take this example… thermal imagers have been used on TV to reveal suspected areas of missing insulation within the exterior walls of a home. The camera picks up the temperature signatures on the wall surface. So when a cold stud (behind the wall) is attached to the wall, the image in that area may show a contrast of colours. What we are seeing is a transfer of heat from a warm surface (wall) to a cooler one, (the hidden stud) and represented as an outline.

This particular application will only be effective if there is a temperature difference of 15 degrees between indoors to the outside. So, if you live in Ontario in during the winter, then the power of this camera can be quite effective.

However, in BC you may not get the same result due to our mild weather. This is certainly useless in the summer when the weather is warm. So question the particular situation when you see this on TV.

Below are some examples of how inspectors can use this technology given the right temperatures and circumstances… based on proper training of course.

Detecting moisture issues 

Water has the ability to either retain heat or cold extremely well. So if there is a leak inside a wall cavity from the outside, and you scan the area, you may be able to see it when the temperature is cold enough.

 Locating areas of heat loss & air leakage

This approach are best utilized when the inside of the home is pressurized and the camera is adjusted to a greyscale palette. When applied and interpreted correctly, one can use this information to improve on energy efficiency, while saving on heating costs.

Seeing electrical issues

With this application, one can look for large temperature differences in service panels and receptacles that cannot be seen by people without the camera. This can be useful for detecting possible fire hazards before they happen.

Finding missing insulation

As mentioned earlier, this is a useful application in the winter, or evening when the temperature difference is suitable.

Locating pests

The camera can easily pick up the body temperature of rodents or other critters in the attic. This can be a super verification tool for pest management companies.

Testing radiant in-floor heating

Thermographic cameras are excellent for looking at the performance of the in-floor heat pipes. After the heat has been on for a number of hours, the outline of the pipes can be seen with absolute clarity. On the flip side, we can easily identify where a leak has formed. Leaks will usually appear as blotchy areas.

Leak in radiant heating


Commercial roofing inspections

This is best done at night, or when the sun goes down. An infrared camera can easily pinpoint any moisture within the layers of the roof insulation or membranes. Note: this is only applicable for flat roofs. This works so well because the water will retain the warmth from the heat of the sun during the day, while the outside air will be cooler… so any trapped moisture will be easy to see.

As mentioned, these specialized cameras are extremely sensitive tools that require adequate training to properly operate & interpret. All findings must be verified for accuracy.

Before hiring an inspector to conduct a thermographic inspection, ask him or her about their training. Ideally, the inspector should have a level 1 certification from a credible and recognized institution. Proper training will take five to seven days on average to complete.

At the end of the day, thermographic imagers/cameras are excellent when used correctly and for very specific applications, so consider whether it is needed, especially if the cost is extra.

For more information or questions, feel free to contact me and I’ll help you out.