What Size Rear Extension Can I Build Without Planning Permission in Manchester?

Thinking about adding extra space to your home? A rear house extension is a fantastic way to increase living space, add value to your property, and improve your lifestyle—without the hassle of moving. But one of the first questions homeowners ask is: “Do I need planning permission?”

The good news is that in many cases, you don’t—thanks to something called Permitted Development Rights. Here’s everything you need to know if you’re planning a rear extension in Manchester.

Permitted Development: What You Can Build Without Planning Permission

Under current rules in England, certain types of home extensions can be built without full planning permission, provided they meet specific conditions. This is known as Permitted Development (PD).

For Terraced or Semi-Detached Homes:

• You can extend up to 3 metres from the original rear wall.

For Detached Homes:

• You can extend up to 4 metres from the original rear wall.

Additional Rules You Must Follow

To qualify under Permitted Development, your extension must also meet the following criteria:

• Height: Maximum of 4 metres for a single-storey extension.

• Eaves Height: Cannot be higher than the existing eaves.

• Roofline: Extension must not exceed the height of the existing roof.

• Materials: Must be similar in appearance to the existing house.

• Garden Coverage: No more than 50% of the total land around the house can be covered by extensions or outbuildings.

• Location: The extension must not be forward of the principal elevation (typically the front of your house).

Larger Extensions – Prior Approval Scheme (Ends May 2025)

Want to go bigger?

Thanks to a temporary Larger Home Extension Scheme, you may be able to build a bigger extension without full planning permission—as long as you apply for prior approval from the local council.

Under this scheme, you can extend:

• Up to 6 metres for semi-detached and terraced homes.

• Up to 8 metres for detached homes.

However, this isn’t automatic. You’ll need to:

• Notify Manchester City Council.

• Go through a Neighbour Consultation Scheme.

• Proceed only if there are no objections (or objections are overruled).

Note: This scheme currently runs until 30 May 2025, so act fast if you want to take advantage.

When Planning Permission Is Required

You will need full planning permission if:

• Your home is listed or in a conservation area.

• You want a double-storey extension.

• Your design exceeds PD size limits.

• You’re planning a balcony, veranda, or raised platform.

Need Help Planning Your Rear Extension in Manchester?

At Builder Manchester LTD, we specialise in designing and building high-quality rear extensions across Manchester and the surrounding areas. Whether you’re looking for a modest kitchen extension or a large open-plan space, we can guide you through every step—from initial designs to construction and sign-off.

Get in touch today for a free consultation and let’s bring your dream extension to life—planning permission or not!