In short, and very simple terms, no – you don’t need planning permission for an extension. As long as it meets a specific set of guidelines, it can be built under Permitted Development.

This is great news if you only want to add a little extra space to your home. Especially when you consider that gaining planning permission for a building project can be a bit of a nightmare. It takes time and money, then there is no guarantee that your plans will be accepted. You may have to start all over again.

It’s important to check that your extension does fall into the permitted developments rights of your local area. If they don’t, you could be served with an enforcement notice ordering you to undo all of the changes. Which would be a bit of a blow!

A brief guideline on Permitted Development

We have written before about permitted development, so sit down with a cuppa and give that a read if you would like more detail. For now, we will just cover the basic rules you need to follow.

  • You cannot cover more than half of the land around the original house.
  • You cannot extend out of the front of your house or towards a public highway.
  • A single storey rear extension can only extend 8 metres back on a detached house or six metres on any other house.
  • The maximum height of a rear extension is 4 metres.
  • A side extension must be single storey and can have a maximum height of 4 metres. The width should be no more than half that of your original house.
  • Materials should be similar in appearance to the existing house.

When do you need planning permission for an extension? 

There are occasions where it may be necessary to obtain planning permission for your extension. These include, but are not limited to:

  • Extensions which are larger than those allowed within the Permitted Development guidelines.
  • Using materials different to those used for your original house.
  • Flats and maisonettes.
  • Converted houses or houses created through permitted development rights to change.
  • Buildings other than houses.
  • Areas with planning conditions or restrictions such as:
  • conservation areas
  • an area of outstanding natural beauty
  • a National Park.

Your local planning authority will be able to advise you on your planning permission requirements.

The Government has announced a possible change to permitted development rights

 At the beginning of the month, Housing Secretary Robert Jenrick announced that a planning permission waiver was being considered. The waiver applies to two storey extensions meaning they could be built under Permitted Development rights rather than needing Planning Permission.

What would these changes mean for homeowners?

 It’s hard to say exactly what to expect from the plans as there hasn’t been much detail released yet. This is what we understand of it so far.

The planned changes would mean that those wanting to extend their home would have far more freedom to do it. They could double the footprint of any extension by pushing upwards as well as out, all without the additional time and cost required if applying for planning permission.

It’s also being argued that growing families would be able to easily extend their homes to meet their changing requirements. It should encourage homeowners to improve rather than move. We can get on board with that!

Are there any downsides to the plans?

I guess it depends on which side of the fence you will be with the proposals put forward. If you are the one planning a new extension you are likely to think the changes are brilliant.

But, if it’s your neighbour building the extension, they could pop up an imposing double storey extension right next to your bedroom window. They wouldn’t even need to ask you whether it’s ok first. So long as the extension meets Building Regulations and planning authority guidelines, there’s unlikely to be a formal route for neighbours to object.

There are also concerns that this move will lead to a boom in unsightly developments. On top of that the government has previously announced that they want to involve communities more in improving housing design. This new measure could somewhat undermine that plan.

Will these changes come into effect?

It is thought that the extended permitted development rules would first apply to purpose-built blocks of flats from January 2020. It would then eventually be rolled out to detached homes.

It must be said that there isn’t currently any formal documentation to back up the plans announced at the Conservative Party conference. Plus, with a looming General Election, whether these proposed changes will come into effect remains to be seen. We’ll just have to keep our eyes peeled.

Get advice

If you are unsure whether your extension falls within the Permitted Development rights, it’s always best to get advice from a professional! Here at JS Building Services, we offer an impartial, no-obligation consultancy service. Our service provides advice on what you can achieve before you commit to a project. This could save you time, money and stress further down the line.