Rawpixel 1054596 unsplash
Written by

How much does it cost to get planning permission for an extension

Last updated Friday 17 May 2019

How much does it cost to get planning permission for an extension

Last updated Friday 17 May 2019


If you’re about to apply for planning permission, or are wondering how fees have changed over the years, worry not!

Our in-house planning team are here to give you the lowdown on all the costs associated with the planning stage of your project.

How much does planning permission cost for an extension?

Costs for planning permission differ, depending on where you are in the UK. To extend your home, you’ll be looking at…

  • £206 within England
  • £190 in Wales
  • £202 in Scotland

These costs apply to alterations / extensions to existing dwellings, and only for one household. So whether you’re going for a classic rear extension, or converting your loft, these are the fees you’ll be paying.

However, if you’re taking on a self build project, costs rise to £462 per new dwelling in England, and £380 in Wales, £401 in Scotland.

Which part of your property are you looking to extend or renovate?

Select an option below to get a quick quote for our services









Two storey

Two Storey



All these costs relate to a full planning application, fees will vary for outline planning permission applications. Outlines are often used on large projects to give the developer an idea of what might be possible before an architect is brought in to provide the details.

Please note: outline planning permission cannot be used to start construction.

Do you need planning permission?

Now, before you get your checkbook out, it’s worth noting that not all extensions require planning permission.

Your home might benefit from your permitted development rights. These are part of a government scheme that allows homeowners to extend their home without the need for planning permission. However, there are strict rules about what kind of developments fall within your permitted development rights.

In order to avoid a full planning application, you’ll need to ensure your extension…

  • Doesn’t extend beyond the rear of the existing house by more than 4 metres, if your home is detached, and 3 metres, if you live in a terrace, or semi-detached property.
  • Only takes up less than 50% of the size of the land around the original house ("original" being the latest of when the property was built or if it was built before 1948, then as it stood on 1st July 1948).
  • Is single-storey, with a maximum height of 4m.
  • Had a roof ridge or top point no higher than the eaves of your property’s roof.

Doing your research for a build project?

Get a custom quote to compare in less than 1 minute!
Get Started

On top of this, you’ll need to bear in mind that permitted development rights can’t be used on these households...

  • Flats and maisonettes
  • Listed buildings
  • Homes in conservation areas

Because of the rules involved with permitted development, and the penalties you could face if these rules aren’t followed, we always recommend getting an architect onboard. They’ll not only ensure your design fits the scheme, they’ll help you apply for a Lawful Development Certificate.

While not a requirement, a Lawful Development Certificate helps prove to both your local authority and future buyers that your extension was legal at the point of construction. This protects you, should the rules around permitted development change in the future.

Lawful development certificates fees are half the price of full planning applications, unless you’re obtaining one retrospectively for work you’ve already constructed. In this case, you’ll need to pay the same price as those listed above.

What some tailored planning advice for your home? Book a free consultation with Resi. We’ll assess your project and lay out your options, all free of charge. We also have our own in-house planning team, so should you choose our services, we’ll even be able to submit your application on your behalf.


Have a Project in Mind?

It takes less than 1 minute
 to get a quote for our services
 to take you through planning
Get an instant quote

Want to know how much your project will cost?

Get an Instant Quote