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• Planning advice 1

House extensions, conservatories, garages and car ports

The following advice is intended for guidance only and assumes that permitted development rights have not been withdrawn by either condition or an Article 4 Direction. If permitted development rights have been removed you will need to submit a planning application for consideration.

To find out if you need planning permission for any of the above developments, answer the questions below:

1. Will the proposed extension be attached to or within five metres of the dwelling?
   
    Yes - go to question 2.
    No - please refer to our planning advice 3 guidance.
   
2. Is the dwelling within a conservation area or is the building to be extended listed or of architectural or historical interest?
   
   Yes - planning permission is likely to be required and you are advised to contact planning services on 443 2381 before starting any work.
   No - go to question 3.
   
3. Will any part of the proposed extension project beyond any part of the existing wall of the dwelling that faces onto a road, pavement or public footpath adjacent to the property?
   
   Yes - go to question 4.
   No - go to question 5.
   
4. Will a minimum of 20 metres be maintained between the proposed extension and the road or footpath that the proposed extension faces?
   
   Yes - go to question 5.
   No - Planning permission is required.
   
5. Will the height of the proposed extension be higher than the highest part of the existing roof of the house?
   
   Yes - planning permission is required.
   No - go to question 6.
   
6. Will the proposed extension together with any other extension to the house, garage or any other building erected since the house was built or built at the same time as the house and which is to remain, cover more than half the curtilage? (curtilage means the front/side/rear garden and driveway but does not include the area of ground covered by the house as first built).
   
   Yes - planning permission is required.
   No - go to question 7.
   
7. Will the height of the proposed extension exceed four metres at a point within two metres of the boundary?
   
   Yes - planning permission is required.
   No - go to question 8.
   
8. Will the extension, including foundations and guttering, be constructed entirely on your own land?
   
   Yes - go to question 9.
   No - planning permission is required.
   
9. Will the proposed extension result in the original house having been extended by:
   
   (a) in the case of a terraced house over 50 cubic metres or 10 per cent of the original volume of the house, whichever is the greater subject to a maximum of 115 cubic metres?
   
   Yes - planning permission is required.
   No - planning permission is not required.
   
   (b) in the case of other properties by 70 cubic metres or 15 per cent of the original volume of the house, whichever is the greater subject to a maximum of 115 cubic metres?
   
   Yes - planning permission is required.
   No - planning permission is not required.
   
   Note: The cubic content of the following should be included in your calculation since they count against the allowance:
   
   (a) any previous extensions which are to remain; and
   (b) any other detached buildings erected at the same time as the house or since the house was built, including garages/car ports, greenhouses, sheds and other buildings/structures which are 10 or more cubic metres and which are at present within five metres of the house or which would be within five metres of the proposed extension.
   
   Cubic content is an external measurement calculated by multiplying length by width by height and must include all of the structure including the roof.