Thermal Survey - Frequently Asked Questions

How does it work?

Read the Frequently Asked Questions to find out more.

Q    How was the map created? 


Between February and April 2013 a specialist plane equipped with a thermal imaging camera flew over the whole Borough on several nights when the skies were clear and the temperature was below 4 degrees. This gave us the best chance of properties being occupied and having the heating on.

The camera provides a picture of the amount of heat a roof is emitting using an infra-red image. A number of images of small areas of the roof were taken and then a calculation was done to arrive at the most commonly occurring.

A property which shows up as emitting a lot of heat could benefit from additional energy efficiency measures such as loft or cavity wall insulation to increase their comfort and reduce their energy bills.

Q    How do I find my property on the map?


In the top right corner of the map page is a box marked “Search”. If you type the number and first few letters of your street name a number of address options will appear, simply choose the one that matches your home. Alternatively you can search by post code.

Once you have found your property you can use the code on the bottom right hand side of the screen to see how it is performing.

If you left click on your property you will see a box with some figures.
This shows the minimum, maximum, average and most common values recorded for your property and a description of whether it is above or below average compared to other properties in Stafford.

Some properties are made up of more than one image. If this is the case you will see a number of values in the pop up box. You can refine your search by zooming in using the scale on the left hand side of the page.

Q    What do the colours and scores mean?


The scores do not represent actual temperatures or amount of energy lost but show a comparison of your property against the average for Stafford.

A property coloured red is emitting more heat than one coloured blue and therefore may benefit from additional insulation.

A property coloured blue is emitting less heat and this could be for 2 reasons - either it is well insulated or it is not being heated (for instance if it is empty).

The values shown for each property are for illustrative purposes only. Whilst they indicate levels of heat loss from a property there are a number of factors that can influence the value - for instance the heating in use on that particular day, the presence of a chimney, roof material.

The average value for both residential and commercial buildings was 40.

Only 7% of properties had an average value of less than 20. 85% had an average value between 20 and 69 and 8% had an average value greater than 69 (see graph below for more details).

The scores have been used to reflect the distribution across the Borough. 


(copied from terms and conditions page - ../thermal-survey-terms-and-conditions)

You can also see the full thermal image of your property by clicking “Thermal Image” in the “Map Settings box” on the left hand side of the screen.

Q    I have loft and cavity wall insulation installed, why is my house still showing up as average or poor?


There may be a point on your roof with a significantly higher score; this might be from a chimney or flue, or it might be from a section of your roof where you have a heat spot for another reason, e.g. a gap in insulation. Other factors can also result in the thermal map showing well insulated properties as average or poor:

  • Building materials influence the level of emissivity. For example, a concrete tiled roof may appear to give out more heat than a slate roof. Surface colour can also have an effect on the actual temperature of the roof covering; dark surfaces tend to absorb and retain more heat than lighter coloured ones.
  • Heat sources such as flues and chimneys or solar panels can increase the average temperature of a roof.
  • The sensor used in the aerial survey may be affected by a nearby tree canopy or vegetation as moisture contained in these features will emit warmer values in or around a roof structure.
  • Moisture on surfaces can cause the imager to pick up the values showing the roof to be warmer that it actually is. This is more likely for flat roofs.
  • Similarly high levels of dirt or profuse mould or moss growth may cause roof materials to look warmer than they actually are.

Q    Why are buildings that have been demolished shown on the map, or why is my extension/new buildings in my area not shown?


The map was made using Ordnance Survey information which was the most accurate information available at the time. New buildings or changes to outbuildings/ extensions may not have been identified by Ordnance Survey at the time the information was gathered, so there can be
inaccuracies which are unavoidable.

Q    Has my privacy been affected by the production of the thermal map?


No conventional photographs were taken; instead the camera captured infrared images of the outsides of properties during the evening, when it was dark. The mapping information (building outlines, roads, outbuildings etc.) used to create the thermal map is based on existing information provided by Ordnance Survey. Google maps already provide far more detailed information than that on our map. However, if you would like to have the colour rating removed from your property we will be happy to do so - please send an e-mail to giving us your postcode and the number or name of your house

Q    Why can't I see the colours on the map, or why do all the colours appear the same on the map?


If you experience a problem viewing the map it may be down to your browser so you could try using another one or visit your local library and use one of their computer terminals. If you want to let us know about any problems you are experiencing, please contact Due to a technical problem, a very small number of properties may unfortunately appear blank on the map.

Q    Where can I get more advice about how to improve the heating and/or insulation of my home?


If you would like more information about the assistance available to improve the energy efficiency of your home you should contact Warmer Homes Stafford on 0800 677 1785.


Related pages
Thermal Survey
How do you rate this page?