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

Biomass Development

8. Biomass development will typically include the fitting of a biomass boiler, biomass storage and possibly the provision of a new chimney or flue. Where works can be accommodated within an existing building/s or do not materially affect the external appearance of a building, then they will not require planning permission. Where they involve the provision of –

• a. an additional building/s to house the equipment and/or store the biomass fuel (biomass ancillary housing); or
• b. a chimney or flue added to an existing building; or
• c. materially affect the external appearance of an existing building,

they will require planning permission. However, this may be provided by permitted development rights provided it does not qualify as an exception as set out below.

8.1. The provision of biomass ancillary housing, a chimney or flue as an enlargement, improvement or other alteration of a dwellinghouse (Class A of Part 1 applies);

A planning application will not be required provided that:

• i. the design and external finishes are in conformity with those of the original dwellinghouse;
• 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 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 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 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 of the original dwellinghouse);
• vii. the building erected is not within the curtilage of a listed building.
  

8.2 The provision of biomass ancillary housing or addition of a chimney or flue 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 where any part of it is 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 ridged 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 within a conservation area, an area of outstanding natural beauty, a National Park, or within the curtilage of a listed building.