Do I need planning permission?

Flats

You will need to apply for full planning permission to carry out a loft conversion which includes any external alterations to the roof.

If your flat is a listed building;(or part of a listed building) you will need to apply for listed building consent to carry out a loft conversion.

Houses

Roof lights

If your loft conversion includes the installation of a roof light, you will need to apply for householder planning permission if:

  • it would protrude more than 15cm above the roof slope (when measured perpendicularly from the external surface of the roof);
  • the highest part of any roof light will be higher than the highest part of the original roof;
  • it would include the installation, alteration or replacement of a microwave antenna, chimney, flue or soil and vent pipe;
  • any new window located in a roof slope forming a side elevation would be clear-glazed and openable if the opening part is less than 1.7m above the floor level of the room to which it is installed; or
  • your property is covered by an Article 4 Direction and it will be installed on the front roof slope (or side roof slope if it faces the road).

Dormer windows

If your loft conversion includes the installation of a dormer window, you will need to apply for householder planning permission if:

  • your property is in a conservation area;
  • it will be installed on the front roof slope;
  • the highest part of the dormer will be higher than the highest part of the original roof;
  • on a terraced house, the size of the dormer would exceed the original roof space by 40m³;
  • on any other house, the size of the dormer would exceed the original roof space by 50m³;
  • other than in the case of a hip-to-gable enlargement, the edge of the dormer closest to the eaves of the original roof shall, so far as practicable, be not less than 20cm from the eaves, measured along the roof slope from the outside edge of the eaves;
  • it would include the installation, alteration or replacement of a microwave antenna, chimney, flue or soil and vent pipe;
  • it would include a balcony, veranda or raised platform;
  • the materials would differ in appearance to those of the existing house; or
  • any new window located in a roof slope forming a side elevation would be clear-glazed and openable if the opening part is less than 1.7m above the floor level of the room to which it is installed.

If your house is a listed building you will need to apply for listed building consent to carry out a loft conversion.

Where can I find further information?

Camden Planning Guidance - Design (pdf)

 

Can I get confirmation that I do not require planning permission?

In situations where you may need to prove, or obtain peace of mind that an existing or a proposed dormer window or roof light is lawful, you can apply for a Lawful Development Certificate

Am I likely to get planning permission?

If you want to find out whether your proposal is likely to be acceptable, you can apply for pre-planning application advice

How do I apply?

You can apply via the national planning portal. To find out what information is required with your application, please see making a planning application

Still not sure whether you need planning permission?

If you need further advice about whether you need planning permission contact the planning advice and information service