Heat loss in your home

Heat loss in your home

In a typical British home up to one third of the heat produced by central heating systems is lost through the roof, walls, floor and windows. For a poorly insulated property, this means that £1 out of every £3 spent on energy is wasted.

How much heat is your home losing?

Is your home well insulated or is leaking heat through your roofs, walls, floors and windows? Are you concerned that you’re paying higher energy bills as a result? The Council wants to help you reduce these bills to a minimum – which should help reduce the Borough’s Carbon Footprint/emissions! 

The Royal Borough of Kensington and Chelsea have been working with ired (an industry-leading team of accredited thermographers based in the UK) to analyse heat loss data in the Royal Borough. 

You are now able to see how much heat your building is losing through its roof by viewing the heat loss map. 

You can find your home by entering the street name into the Search box, see the amount of heat lost from your roof and compare it with others in the neighbourhood.  

By identifying properties with high levels of heat loss the borough will be able to raise awareness of energy efficiency and put in place measures to reduce fuel poverty and instances of condensation and mould; improve health and thermal comfort and help residents save money on their fuel bills. 

Heat loss map

The Council commissioned geographic imaging company BlueSky to undertake an aerial thermal survey (on 1st February 2015) of the heat loss of buildings across the borough. Individuals and specific property details cannot be identified. The results are shown in the thermal image map below and give an indication of how much heat is being lost or ‘leaking’ from a property. 

Buildings have different colours and the colours represent the relative difference in the temperature of properties' roofs across the borough (i.e., whether a property is losing more or less heat than the average of the survey). It also shows borough and ward boundaries as well as a heat loss classification table ("Legend") with a sliding scale of heat loss.

This heat map is a useful tool but it is not infallible – it should only be used as first step in finding out how much heat is being lost.


What does the colour Red mean?

The nearer a property is to red, the higher the heat loss. The properties coloured in red are emitting more heat than the ones coloured blue. Therefore they may benefit from additional energy efficiency measures such as loft or cavity wall insulation, to increase their comfort and reduce energy bills.

What does the colour Blue mean?

The nearer a property is to blue, the lower the heat loss. The properties coloured blue are emitting less heat and this could be for two reasons, either they are well insulated or are not being heated. For example, they may be empty or unoccupied.

How is the scoring calculated?

The scoring of properties is based on the relative difference in the temperature of properties’ roofs across the borough i.e. whether a property is leaking more or less heat than the average of the survey.

Explaining the thermal data (disclaimer)

Please note that the thermal data is showing relative heat loss from buildings, so the values for each property are for illustrative purposes only. Therefore, all recommendations are advisory and for guidance only and are based on the information available at the time of the inspection. Whilst they indicate levels of heat loss from a property/building, there are a number of factors that can influence the value and should be considered when looking and interpreting an aerial thermal image as per below:

  • How many people were at home on the night of the survey
  • Whether the heating was turned on o the night of the survey
  • The building materials used in constructing the property; presence of a chimney, roof material etc. 

This means a poorly insulated property may appear not to be losing much heat because it was unoccupied, the residents were on holiday that night or there was no heating on; whereas a well insulated property may appear to be losing a lot of heat because the residents were having a party that night. However, the Council’s aim in publishing the aerial thermal heat loss maps is to raise awareness on the importance of insulation and to encourage residents to install energy efficiency measures. 

How to prevent heat loss

Find out how to prevent heat loss in your home on the Preventing heat loss page.

Last updated: 1 February 2024