As mentioned previously, not all property developments require planning permission. However, it is important that you check with the local council planning department whether your planned extension requires permission, as it could be very costly if you carry out some building works which later have to be altered or even demolished because you failed to obtain the correct planning permissions. It is best to take the advice of an architect or planning consultant.
The rules for when planning permission in England changed in October 2008. A complete list of the specifications is not covered within this section, however the list below can be used as general guidance.
Extension to a House
In England Planning Permission is not required as long as:
- The proposed footprint does not exceed 50% of the total curtilage;
- The height would not exceed the highest part of the existing roof;
- The height of the eaves would not exceed the existing eaves height;
- The elevation does not front a highway;
- The maximum eaves height of the extension is less than 3m if it is within 2 metres of the boundary;
- The proposed extension does not exceed 4m in height or have a width greater than half the width of the original house:
- The proposed extension does not consist of –
- the construction or provision of a veranda, balcony or raised platform;
- the installation, alteration or replacement of microwave antenna;
- the installation, alteration or replacement of a chimney, flue or soil and vent pipe;
- the alteration of any part of the roof of the original dwelling house;
- The materials used are similar to the existing house.
In Wales Planning Permission is not required as long as:
- The proposed extension does not exceed 70 cubic metres in the case of a detached or semi detached house or 50 cubic metres in the case of a terraced house (these figures include previous extensions or additions within 5m of the original house);
- The proposed extension does not exceed 4m in height and is within 2m of the boundary;
- The proposed extension is not closer to any highway than the original property unless it is at least 20 metres away from such a highway. This includes any public right of way including bridle paths and footpaths;
- Half the original amount of land surrounding the house is not coveredby additional buildings;
- The extension is not higher than the highest point of the original house.