Information Leaflet # 12
Renewable Energy Development within the Curtilage for a Dwelling House-Permitted Development Rights
August 2006

Solar Collectors

7. Solar collectors include solar water heating panels (SWH) and photovoltaic panels (PV)

7.1 Solar collectors fitted to the wall of an existing dwellinghouse. (Class A of Part 1 applies);

A planning application will not be required provided that:

• i. their design and external finishes are in conformity with those of the original dwellinghouse; If your dwelling is located within a Conservation Area you should discuss your proposals with your local Planning Office;
• ii. the cubic content of the resulting building does not exceed the cubic content of the original dwellinghouse –
• (a) in the case of a terrace house or in the case of a dwellinghouse in a conservation area, by more than 50 cubic metres or 10% whichever is the greater;
  (b) in any other case by more than 70 cubic metres or 15% whichever is the greater; or
  (c) in any case by more than 115 cubic metres;
• iii. the solar collectors or other enlargement, improvement or alteration do not cause the part of the building enlarged, improved or altered to exceed the height of highest part of the existing roof;
• iv. the solar collectors or other enlargement, improvement or alteration do not cause any part of the resulting building to be nearer to any road which bounds its curtilage than the part of the original dwellinghouse nearest to that road;
• v. the solar collectors or other enlargement, improvement or alteration do not cause the part of the building enlarged, improved or altered to exceed 4 metres in height where it is within 3 metres of the boundary of the curtilage;
  
• vi. the total area of ground covered by buildings within the curtilage (other than the original dwellinghouse) does not exceed 50% of the total area of the curtilage excluding the ground area fo the original dwelling house);
• vii. the building erected is not within the curtilage of a listed building.

7.2 Solar Collectors fitted to the roof of a dwellinghouse (Class B of Part 1 applies);

A planning application will not be required provided that:

• i. their design and external finishes are in conformity with those of the original dwellinghouse;
• ii. the fitted collectors do not cause any part of the dwellinghouse to exceed the highest part of the existing roof; (see paragraphs 7.4 and 7.5)
• iii. the fitted collectors do not cause any part of the dwellinghouse to project beyond the plane of any existing roof slope fronting a road by more than 15 cms.
  
• iv.the dwelling house is not in a conservation area
• v. when fitted, the collectors do not increase the cubic content of the dwellinghouse by more than 20 cubic metres, in the case of a terrace house or 25cubic metres in any other case; or the cubic content of the resulting building does not exceed the cubic content of the original dwellinghouse.
• (a) in the case of a terrace house by more than 50 cubic metres or 10% whichever is the greater;
• (b) in any other case by more than 70 cubic metres or 15% whichever is the greater; or
• (c) in any case by more than 115 cubic metres;

Where the solar collectors are on a flat roof the proviso at 7.2 iii applies. See also general commentary on height and flat roofs at 7.4

7.3 Solar collectors fitted to other buildings within the curtilage of a dwellinghouse ( Class D of Part 1 applies).

A planning application will not be required provided that:

• i. the building altered or provided does not become nearer to any road which bounds the curtilage of the dwellinghouse than the part of the original dwellinghouse nearest to that road;
• ii. the building altered or provided does not have a cubic content greater than 10 cubic metres and any part of it is not within 5 metres of any part of the dwellinghouse;
• iii. the height of the building altered or provided does not exceed 4 metres in the case of a building with a redged roof or 3 metres in any other case.
• iv. the total ground area covered by the buildings altered or provided ( other than the original dwellinghouse ) does not exceed 50% of the total area of the curtilage ( excluding the ground area of the original dwellinghouse);
• v. the building altered or provided does not have a cubic content greater than 10 cubic metres where it is on land eithin a conservation area, and area of outstanding natural beauty, a National Park, or within the curtilage of a listed building.

7.4 It should be noted that the highest part of the roof refers to the dwelling as a whole, not the particular part of the roof where the panel is to be fitted. The highest part of the roof is determined by the height of the highest ridge tile on a pitched roof, or in the case of a flat roof the height of its top surface. Where the dwellinghouse has both pitched and flat roofs it will be determined by whichever is the highest.

7.5 In order to be permitted development, any new work should not exceed the height of the highest ridge tile on a pitched roof, or in the case of a flat roof the height of its top surface. A parapet is taken as being part of a wall, not the roof. A chimney is similarly not part of a roof, and its height does not determine the highest part of the roof. Decorative appendages such as finials also do not determine the height. In the case of flat roofs it is normally accepted that the top surface of a rooflight may be counted towards height and that a rooflight forms part of a roof.