Can Thermal Cameras See Behind Walls?

Detecting Heat Behind Walls

A common question regarding Thermal Cameras are;

  • Can it see through walls
  • Detect moisture through floors
  • See hot or cold lines through the wall
  • Check a leak through the ceiling

The answer is yes and no.

While Thermal Cameras cannot see through walls or glass, as they will detect the surface temperature of the first solid material you point at, what they can see is the heat given off (or taken away) from sources close to the wall giving us information about what is going on behind the wall. This would essentially enable you to be able to see what's going on inside or behind the wall and give you a lot of information that we cannot see with the naked eye.

Checking for Thermal behind Walls, Floors or Ceilings

As mentioned above, it's not possible for any thermal camera to see through any solid object. So how it works is that there is an object or substance that is causing temperature variance on the wall, floor or ceiling. 

To check this; a wall, floor or ceiling has a uniform temperature which means that under normal circumstances the temperature is the same across the whole surface. 

However, if you suspect poor insulation or wish to detect pipes behind the wall, this is possible. 

Let's assume you have the heating on inside a room and its freezing cold outside. if there are holes in your insulation it will show up in blue spots on the screen compared to the rest of the surface. A well-insulated house will have uniform temperature across windows, doors, and walls throughout the day.

Thermal camera looking at insulation

 Thermal image of heat behind the wall

Thermal cameras focus on the infrared heat energy and converts it into colors that represent the different level of heat on the thermal images. Brighter colors such as red, orange or yellow represent warmer temperatures while darker colors like purple, blue or black indicate colder temperatures. From the image above, you can see that the television and the sofa are warmer compared to other objects. You can also see that parts of the wall are cooler than others and this is how it can detect what's happening behind a solid object, in this case, a wall. 

By looking at the infrared image of the surroundings of the house, inspectors can tell whether insulation is needed or not by checking for things such as heat loss or air leakages. Other factors to be considered would be weather conditions or the shape of the home. To check if there are any gaps in the walls, inspectors would usually perform a test called blower door test, which would be done to check which exact spots causes the air leakages so that the necessary action can be taken.

An Infrared image of the wall will visibly show the drywall screws because of the difference in temperature between the drywall and screws. The same can be seen for the studs since wood releases heat at the different rate than metal screws and drywall. The temperature range can be adjusted depending on which part you would like to see more details of, whether it be the screws or the studs.

To have a well insulated home, inspections such as energy loss, HVAC, moisture, roof leaks and plumbing leaks should be inspected in addition to just inspecting the heat radiation behind walls. Thermal images can also see the differences in temperatures caused by insects, mold and moisture. With a good understanding of thermal imaging and the help of a knowledgeable inspector, any insulation problems can be quickly solved.  

Detecting Radiant Heat

Radiant Heating is is commonly used system in many places, including residential homes or commercial/office buildings. They are mostly used in buildings with many floor and are used most often during the colder seasons. These hot water supply pipes are not visible to the eye as they are located beneath the floor, which makes it easy to be ignored or forgotten. It is very important to keep an eye out for it and should be monitored on a regular basis, i.e. at least once a year. Thermal cameras can be used to monitor the situation to make sure the pipes are working properly and efficiently locate if or where the radiant heat leakages exist. 

If a radiant heat leakage is present, it can use up a lot of energy and cause major property damage if it is not repaired in time. It can take up a long period of time and a lot of money to identify the exact location of a leaking hot water pipe and it is quite the physical process of tearing up or breaking up big areas of the flooring in order to locate the exact location of a leaking hot water supply pipe if not identified early. The more time it took to locate the leaking pipe, the more costly and difficult it would be to settle and repair the damages caused.

After detecting problems such as leakages, it is important to take action to fix the issue immediately. This can reduce and prevents further damage which would save you time and money. 

Detect Moisture with Thermal Camera

By identifying the variance in temperature between a wet area and the surrounding dry areas thermal imaging can help locate moisture issues that would not be visible during a limited visual home inspection. Moisture is nigh impossible to spot with the naked eye. You don't know its there until its too late and the room is moldy and products contaminated. Thermal Cameras do a great job in helping inspectors or site operators to inspect critical locations and check for moisture, before its too late. 

To do this; simply scan locations prone to moisture exposure with the thermal camera and check if the heat is uniform. Places with moisture will show up colder to the surrounding area as the water draws away the heat. This can be picked up with a thermal camera or imager enabling preventative actions to tackle the issue. 

PerfectPrime has a selection of thermal imaging cameras that are perfectly suited for detecting heat behind walls. Check out our selection here: https://perfectprime.com/pages/thermal-imaging-camera