FAQ - Planning

1. Can I build an extension without planning permission?

Broadly speaking, you don’t need planning permission for the construction of an extension or conservatory when it is to the rear of the house. However, you need to me these guidelines:

• Terraced and Semi-Detached Houses: If the house has not been previously extended, the floor area of the proposed extension cannot exceed 40sqm. This exemption also allows for extensions above ground-floor level (if the house is semi-detached or terraced, the area of the above ground extension cannot exceed 12sqm). This means, for a typical semi-detached house, one could have a ground floor extension of 28sqm and 1st floor extension of 12sqm without applying for planning permission. Any above ground floor extension shall be a distance of not less than 2 metres from any party boundary
• Detached Houses: The overall area of extension must be less than 40sqm. This exemption also allows for extensions above ground floor level, the area above ground floor cannot exceed 20sqm. One could therefore have a ground floor extension of 20sqm and a 1st floor of 20sqm. Any above ground floor extension shall be a distance of not less than 2 metres from any party boundary
• Both Cases: If the proposed extension is in addition to an existing extension overall areas of all extensions must not be more than 40 sqm, including extensions which needed permission, e.g. to side of house.

2. Can I cover my entire back garden with an extension of 40sqm?

No. The extension shall not reduce the "Private Open Space" of the back garden to less than 25sqm. Hard surface areas to the rear of a house are exempted development, providing they are used for a purpose incidental to the enjoyment of the house and not used for the parking of cars. Existing or proposed garden shed/s are not reckoned as private open space.

3. What height can I build my extension without permission?

The highest point to which the wall of an exempt extension can be built is eaves level. If the proposed extension has a flat roof, it must not exceed the eaves or parapet level. If the proposed extension has a pitched roof, it must not exceed the ridge of the existing pitched roof.

4. Can I build a window to the side of my extension?

Yes, providing the following guidelines are applied:

• Terraced and Semi-Detached Houses: Windows at ground floor level shall not be less than 1 metre from the boundary they face. Windows at above ground floor level shall not be less than 11m from the boundary they face. The above applies to terraced s/d dwellings.
• Detached Houses: Where the dwelling is detached and the floor area of above ground floor extension is greater than 12sqm windows shall not be less than 11m from the boundary they face.

5. If I build an attic conversion do I need permission?

Not usually, however, permission is needed if work involves dormer windows. If velux windows are proposed to the rear, it is exempt. If velux windows are proposed to the side/front elevation it is not exempt.

6. Is the area of an attic conversion reckonable in assessing the 40sqm exemption limit for domestic extensions?

No.

7. Can I build a balcony / roof garden on my extension without permission?

No.

8. Can I build a garden shed on my property without permission?

Yes, provided that:

• It is not forward of the front wall of the house;
• Not greater than 25sqm (or no. of sheds aggregated);
• 25sqm of garden space is left. N.B. extensions attached to house are not reckoned as private open space;
• Shed finish is in keeping with the house;
• Shed height: max 4m pitched roof; 3m flat roof;
• It is not lived in or used for keeping of animals (pigs, ponies, horses, pigeons).

9. Can I build a porch without permission?

Yes, provided that:

• Not less than 2 metres from roadway;
• Not more than 2sqm height: 3m max for a flat roof, 4m max pitched roof.

10. Can I build an extension to the side of my house without permission?

No. Not exempted development. However an existing garage to the side may be converted (see above).

11. Can I build an extension to the front of my house without permission?

No. Not exempted development (except the porch - for exemptions see above).

12. Can I build walls around my house without planning permission?

Yes. Subject to:

• Not more than 2m high to the rear.
• Not more than 1.2 metres to the front or forward of the front of the house.

NB: Metal palisade or other security fencing is not exempt.

13. Can I convert 2 or more dwellings to use as a single dwelling without permission?

Yes. But only if the structure was previously used as a single dwelling. e.g. a house which was used as a single dwelling when built, later converted to flats can convert back to single dwelling use under this exemption.