ePrivacy and GPDR Cookie Consent by Cookie Consent Do you need planning permission for an extension?

Do you need planning permission for an extension?

5 min read
Oct '25 • by Heather

Quick summary

Whether you need planning permission for an extension depends on your project and property type. If your rear extension is less than 3 or 4 metres long, uses similar materials, and covers less than 50% of your land, you likely don’t need permission. But if you live in a flat, listed building, or conservation area, or if your project exceeds these limits, you’ll need to apply, which costs around £100 and takes about 8 weeks.

If you are looking to extend your home, you’ve no doubt been thinking about planning permission. Namely whether or not you will need it, the rules you’ll need to follow and how much it will all cost.

Our in-house planning experts have produced this updated guide…

Do you need planning permission? Maybe not.

Whether or not you can extend your home without planning permission will depend on your permitted development rights. These rights, created by the government, allow homeowners to extend without a planning application as long as their project adheres to the following strict set of guidelines.

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