Why Every Home Inspection Needs to Include Infrared Thermography

Why Every Home Inspection Needs to Include Infrared Thermography

Why Every Home Inspection Needs to Include Infrared Thermography

Thermal Photography Reveals Faults Otherwise Hidden

Home performance professionals have many valuable tools at their disposal, but none are cooler than the thermal camera. Infrared Cameras, or IR Cameras, are used to detect possible defects in buildings without destroying anything. They can sense temperature differences down to a fraction of a degree. It is important to remember that these cameras only see temperature difference, and it takes a trained eye and some additional investigation to see WHY there is a difference in surface temperature.

AIR INFILTRATION

The first two photos below the dog, show a vaulted ceiling covered with knotty pine tongue and groove boards; a pretty and dramatic looking ceiling. The bottom picture, however, shows that there is no drywall behind the boards and thus no air-barrier to keep the heat in the room from leaking out into the attic. This ceiling may also be a fire hazard because the drywall is meant to be a flame spread barrier. Some drywall also has a radiant foil backing to reflect some of the summer heat. The ceiling is also very poorly insulated with what appears to be fiberglass batts. This defect would be entirely invisible without the help of the IR Camera and makes it much less appealing.

To best detect air infiltration issues like those in this ceiling, many home performance professionals will run a blower door while they are doing the thermal inspection. The blower door depressurizes the house, causing any air leaks to pull outside air into the house. The movement of air over the interior surfaces causes them to cool down and thus show up as blue or black spots on the IR image.

MISSING INSULATION

Why Every Home Inspection Needs to Include Infrared Thermography

The next two pictures show an uninsulated porch cap that is allowing heat from the house to escape to the exterior and even keep the sidewalk above freezing. It is quite common to have foundation walls that include the space under the porch, but best practice is to insulate the poured floor of the porch from the basement to prevent heat loss. While this might seem handy in areas with snow and ice, the energy loss in dollars is not acceptable.

These last few photographs really show a situation where thermography is so helpful. This house had a slightly damp corner in the basement. The baseboard was warped just slightly and the carpet was damp. Since it was a fully finished basement with drywalled walls and ceiling, the only other way to see what’s going on would be to start cutting holes and fishing for the problem. As you can see from the thermal image, there is a large cold spot near the top of the wall, and a small trail of cold running down the left side of the stud cavity. Going outside to see what might be causing the problem, we notice that there is a hose bib on the outside right at that spot. Some destructive investigation is still needed, and will have to be done anyway to access the area and make the repair, but it’s a pretty safe bet that the hose faucet has a small leak and needs to be replaced.

If you are signing up for a home inspection or energy audit, DEMAND that your inspector have and use a thermal infrared camera. Most will charge a little extra for the service because the cameras cost thousands of dollars, but the additional information is priceless and will help you make better decisions about your home.


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