Thermal imaging mapping of your property

How much heat is your home losing?

An aerial heat loss survey of Spelthorne borough was captured in November/December 2013.

The survey enables residents to gain an indication of how much heat their house is losing.

The colour on the map represents 9 different levels of heat loss from properties within Spelthorne borough. These nine levels have been grouped into three categories (high, moderate and low heat loss). The Heat loss index is an average value of how much heat is being lost from the building, relative to the rest of the area surveyed.

It is important to bear in mind the following points when looking at the results of the survey:

  • the image is a snapshot of how much heat a property was losing when the survey was undertaken

The amount of heat a building loses can be influenced by many factors:

  • whether the heating was on during the night of the survey
  • the building materials used in constructing the property
  • pockets of warm air caused by heat loss through walls or from nearby buildings
  • what effects the heat loss from a building is mostly down to the level of heating on in the property (or not as the case might be), and the effectiveness of the insulation in the roof.  It is important to remember that a low heat reading (which looks like a good insulation result) might be down to the fact that no heating was on at the property prior to the survey taking place - ie occupants away, vacant properties, or residents simply not having their heating on

High Heat Loss - 170-255

The building has high heat loss, which means a large proportion of heat from the building is escaping through the roof of you property. Money can be saved on fuel bills by installing cavity wall and loft insulation and even simple draught proofing measures.

Moderate Heat Loss - 85-169

The building has moderate heat loss, which means some heat is escaping through the roof. You may have installed some insulation within the property, however, there are additional measures which can be taken to reduce your energy bill. For instance, you may need the insulation in your loft topping up, or re-programming your heating controls may also help reduce your energy bills.

Low Heat Loss - 0-84

The building has low heat loss, which is an indication that the building is well insulated with minimal heat loss. In some cases, the building may have been vacant during the time of the survey with no heating on, or the building may have little heating on. There may still be some improvements you can make on saving energy within your property, for instance, turning lights off when not required or reducing the temperature of the building.

Did you know that 25 per cent of the heat lost from your home is through an uninsulated roof? And another 35 per cent is lost through uninsulated walls? Improving the insulation of your property can save you money on your fuel bills. For information and advice on how best to insulate your property please contact Action Surrey energy advice service on 0800 783 2503 or visit