When Do I Need Planning Permission for an Extension?

Permitted Development Rights for Extensions

The good news is, many home extensions can be built without needing formal planning permission, thanks to Permitted Development Rights. However, there are some conditions and limits to be aware of:

• Single-Storey Rear Extensions:

  • You can extend up to 4 metres for a detached house and 3 metres for a semi-detached or terraced house.
  • For a temporary period under Neighbour Consultation Scheme, the extension can be up to 8 metres for a detached house and 6 metres for others (but you need to notify the council).

• Height Restrictions:

  • The extension must be no taller than the existing house.
  • Maximum height is 4 metres if extending to the rear.

• Side Extensions:

  • Single-storey only.
  • Maximum height of 4 metres.
  • Width must be no more than half the width of the original house.

• Two-Storey Extensions:

  • Must be at the rear and no closer than 7 metres to the rear boundary.
  • Must match the materials of the original house.

• Maximum Coverage:

  • Extensions and other additions must not cover more than 50% of the land surrounding the original house.

When Planning Permission Is Required for an Extension

Even with Permitted Development rules, there are situations where you will need planning permission:

1. Listed Buildings & Conservation Areas:

   • If your property is a listed building or within a conservation area, National Park, or Area of Outstanding Natural Beauty (AONB), planning permission is almost always required for extensions.

2. Front Extensions:

   • Extensions that go beyond the principal elevation or towards a road will need planning permission.

3. Height Limitations:

   • If you want your extension to be taller than the existing house, planning permission is required.

4. Non-Domestic Use:

   • If the extension will be used for business purposes or as a separate dwelling, you’ll need permission.

Building Regulations vs Planning Permission

It’s crucial to understand that even if your extension qualifies under Permitted Development, you will still need to meet Building Regulations. These cover the safety and structural integrity of your build, such as fire safety, foundations, ventilation, and electrical wiring.

Planning Permission for Extensions in Special Areas

If your home is in a conservation area, an AONB, or a National Park, your Permitted Development Rights are more restricted. Often, you’ll need to apply for planning permission even for relatively small extensions. This is because these areas are protected to maintain their unique character.

If you live in a listed building, planning permission is required for almost all types of extensions, as listed buildings are protected due to their historical or architectural significance. Always consult your local planning authority if you’re unsure about your property.

The Neighbour Consultation Scheme

For larger single-storey rear extensions, you may be able to build without planning permission through the Neighbour Consultation Scheme. This allows larger extensions under Permitted Development, but your neighbours will be notified, and if they object, the council will decide whether the extension can go ahead.

Getting Professional Help

Navigating planning permission can be tricky, but you don’t have to do it alone. Here at SurvEssex, we’ve helped countless homeowners expand their homes with seamless planning and extension plans that are fully compliant and council-ready. We offer a fixed-price guarantee so you know what to expect with no surprises. With our experience, we can take the stress out of the planning process and help you get your extension right the first time.

Summary: When Do I Need Planning Permission for an Extension?

You do not need planning permission if your extension falls under Permitted Development Rights, such as most single-storey rear extensions or side extensions within the height and width limits.

However, planning permission is required if:

• Your property is listed or in a conservation area.
• The extension is at the front of the property.
• The extension exceeds height or size limitations.
• You intend to use the extension for business or non-residential purposes.

Always make sure your extension is within regulations to avoid fines, delays, or having to undo all your hard work!