Thermal imaging shows poorly insulated homes in London

Thermal images taken on a CAT S61 smartphone in London show a vast amount of heat loss from homes across the city during the winter period this year.

The images were captured as part of a project studying insulation of homes throughout the country. In a typical British home, around one-third of the heat produced by its heating system is rapidly lost through the roof, ceiling and walls. The picture below captures well-insulated walls and roof of a new build adjacent to a poorly insulated Victorian building in London.

Paul Holmes, Technical Product Manager at Bullitt Group, makers of the Cat S61, said: “When looking 

at a building using thermal imaging, it’s the contrasting colours that are important to focus on. Yellow and white/yellow spots show heat, and dark plum colours show cold spots. Both of these can be a bad sign because it usually means that either heat is escaping or cold is coming in.

“The lighter or brighter a patch is, the hotter it is, and the bigger the colour difference the bigger the difference in temperature.

Equally, from the outside of the house it’s important to take note of particularly warm spots as this could be a sign of heat escaping. In general, the goal is for the exterior of your house to be cold – including windows, external walls and the roof – as this means that the heat is staying inside rather than leaking out.”