These shocking images show just how much energy the nation is losing - through poor roof installations, unreliable glazing and outdated window frames.
New build homes, office blocks and high street shops in the UK were targeted with a thermal imaging camera to examine how much heat was leaking out.
Office blocks were found to be a repeat offender thanks to open staircases, large glazed doors and fire escapes which allow heat to escape and are notoriously colder areas of a building.
The images, compiled by glass and glazing manufacturer Pilkington Ltd, show a scale to the right of the thermal shot which indicates heat loss.
The white areas of the pictures are the hottest on the scale, indicating where the most heat is leaking from the home.
As the image fades to orange and then dark blue this highlights the coolest areas, where less heat is escaping.
Julia Berkin, from Pilkington, said: "It's interesting to compare the different types of buildings and shocking to see how easily energy is being lost.
"Over the course of a day or a week, losing heat energy through a door, window or roof might not make much of a difference.
"But over years or decades, those little bits of heat leaking out will add up to have a huge impact on your energy bills.
"In a time when people are caring more and more about their carbon footprint and don't want to waste energy, efficient windows are an important upgrade for both new and existing homes.
"Ultimately the correct installation will save money on energy bills, make a home or building more comfortable and is an easy way for individuals to help the current climate."
The images show that residential front doors are a huge source of energy drain for their occupants, glowing bright white in the pictures.
And older buildings, such as a thatched house, are losing masses of heat at the gable ends where they meet the roof.
The variety of images were shot in and around Coventry to show the different building types in the average city.
And the thermal scan of the Coventry Telegraph's offices shows the majority of heat leaking from its large wooden door.
Julia added: "It can be a real style choice to use old-fashioned decor like a thatched roof or big wooden door.
"But these images show that they're not always the best in terms of insulation or keeping heat in.
"That said, some of the more modern houses we've seen images of also don't perform brilliantly in terms of heat retention."
