A Guide to Permitted Development Rights

If you're thinking about taking up a house extensions project it's important to know the rules if you don't have planning permission. Our guide to Permitted Development Rights explains extension styles you can build without the need to apply for any planning permission.

By Gemma Parkes | 19 June 2018

Find out what extension styles you can build without the need to apply for any planning permission.

linked house extension coopersale

Image: Clear Architects, cleararchitects.co.uk

Permitted development allows you to extend your home without requiring full planning permission, providing you adhere to certain guidelines relating to the size and appearance of your new addition.

In some areas (classed as designated land), such as conservation areas, national parks, Areas of Outstanding Natural Beauty and world heritage sites, PD rights can be removed, so it’s always best to check with your local planning authority if these allowances apply.

Regulations also differ between England, Wales, Scotland and Northern Ireland. Do bear in mind that any new extension, even when done under the development rules, will still have to meet building regulations.

We outline the type, style and look of extensions you can build without planning permission , explain why it’s important to Lawful Development Certificate, and why you should a closer look at the Permitted Development fine print.

What extensions can you build without planning permission?

rear kitchen extension

Image: MW Architects

  • Side-return Extension: This style must have a maximum height of four metres and a width no more than half of the house.
  • Rear Extension: Recent changes to PD guidelines in England mean that in most areas (not on designated land) you can now add a single-storey rear extension up to eight metres from the original rear wall of a detached house (previously it was four metres), or six metres from all other houses, such as semi-detached or terraced properties (previously three metres).

However, this is only a temporary change to the regulations. Any extensions built under permitted development must be completed by 30th May 2019 or risk losing out.

  • Double-height Addition: At present, two-storey rear extensions are also possible (not on designated land), although anything you build must not extend beyond the back wall of the original house by more than three metres or be within seven metres of any boundary opposite the rear wall. However, under proposed legislature, double storey extensions could be allowed under permitted development rights, where neighbours and planning officials will no longer be able to formally object to plans.
  • Loft Conversion: To fall under Permitted Development rights, repurposed attic space must not exceed 40 cubic metres for terraced houses or 50 cubic metres for detached and semi-detached houses.