What are thermal imaging cameras, and why should they matter to you? Well, a thermal imaging camera or infrared digital camera is essentially a camera that detects heat. It can see temperatures.

The infrared is a region of the electromagnetic spectrum, just like the visible light you see, but it has slightly lower energy. This means that our bodies interpret infrared radiation as heat rather than light. But how can you see heat? This is exactly what a digital thermal camera does. It’s not that different from the digital camera you use to take your holiday snaps, except for the wavelength of the radiation it detects. You can use this to take images where there is no natural light. For example, if you took a picture of a person in dark room with an ordinary digital camera with a CCD designed for visible light, you would see nothing, but using a thermal camera with a CCD specially optimized for the IR you get an image of the person, with the hot areas of their body, like the face and hands, glowing more brightly than the covered areas. This is because those areas are where the body loses heat, and in doing so emits infrared radiation.

This technology was traditionally used by the military and security services because it lets you detect sources of heat like people, animals etc in places where normal cameras would fail. This technology is now becoming more mainstream, and a modern digital thermal camera looks a little bit like a camcorder. Now that thermal cameras are more sensitive and portable, unlike the early models which had to have built in cooling and so were much bulkier, the applications for this technology are ever expanding. One of the biggest growth areas for the use of thermal vision cameras, is in assessing the energy-efficiency of buildings, sometimes called a green audit.

When you heat your home in winter some part of that heat always escapes the building, through the walls due to lack of cavity insulation, or through the roof if the loft isn’t well insulated, leaking into the colder surroundings, so losing energy. If you can identify the exact location of these leaks, then it is much easier to efficiently insulate your home and prevent the loss of heat and energy. Not only will this reduce the amount of energy you use by up to 15%, cutting your carbon footprint significantly, but it can also save you money. Of course, you could just renew all the insulation in you home, which will definitely cut your energy usage and costs, but it is also an expensive endeavour.

Wouldn’t it make more sense to find out where best to place the insulation for optimum effectiveness? This is what a thermal imaging inspection using a thermal camera can help you do, by looking for hot-spots in the building exterior, that indicate heat is escaping. These hot spots show up a white or yellow on a thermal imaging camera, and cold spots, which if they are inside a building can show a heat sink, where energy is being lost, would show up as black.  Infrared inspection can also include a blower door test. This is when a blower is used to push air through defects in the building shell, often around doors or windows. This increases the leak, making it easier to spot with the infrared camera, where it shows up on the viewfinder as black streaks. Global warming is a major challenge facing the planet, and using thermal imaging in a thermal infrared inspection can not only help us meet that challenge but can also save you money!

by Kati-Ann Meade