What’s Permitted Development and How Can I Use It?

This comprehensive guide from Rosebrick Developments explains permitted development rights in 2025 – your legal right to extend or improve your home without needing full planning permission. We cover exactly what you can build, size limits for different property types, the larger home extension scheme, and when these rights don’t apply. Understanding permitted development can save you thousands in planning fees and months of waiting time.

Key topics covered:

  • What permitted development rights are and how they work in practice
  • Exact size limits for extensions, porches, and outbuildings by property type
  • The larger home extension scheme and prior approval process
  • When permitted development rights don’t apply and what to do instead
  • Common mistakes that invalidate your rights and how to avoid them
  • How building regulations still apply even with permitted development

What Exactly Are Permitted Development Rights?

Permitted development rights are your legal entitlement to make certain changes to your property without needing planning permission from your local council. Think of it as a blanket planning permission granted by the government rather than your local authority.

The key thing to understand is that these rights exist to let you make reasonable improvements without the expense and delays of formal planning applications. They cover common home improvements that typically don’t harm neighbours or the wider environment.

However, these rights come with strict rules about size, height, location, and materials. Step outside these rules, even by a small amount, and you’ll need full planning permission.

Can I Really Build an Extension Without Planning Permission?

Yes, but only if your extension meets specific criteria. Here’s what you can actually build under permitted development:

Single-Storey Rear Extensions

For detached houses, you can extend up to 4 metres from your original rear wall. For terraced, semi-detached, and other house types, the limit is 3 metres. The extension can’t be higher than 4 metres and must use materials similar to your existing house.

Side Extensions

Single-storey side extensions are allowed up to 4 metres high, but they can’t be wider than half the width of your original house. All multi-storey side extensions need planning permission.

Porches

You can build a porch up to 3 square metres in floor area and 3 metres high, as long as it’s at least 2 metres from any highway boundary.

The critical measurement is from your “original house” – meaning as it was first built or as it stood on 1 July 1948 if built before then. Previous extensions count against your allowances.

How Big Can I Actually Go With the Larger Home Extension Scheme?

This is where it gets interesting. The larger home extension scheme, introduced during the pandemic and made permanent in 2020, doubles your extension allowances if you follow the right process.

Under this scheme, you can extend:

  • Up to 8 metres for detached houses (instead of 4 metres)
  • Up to 6 metres for terraced, semi-detached, and other houses (instead of 3 metres)

But there’s a catch – you need “prior approval” from your local council, which includes consulting your neighbours. This isn’t the same as planning permission, but it does add time and cost to your project.

What’s This Prior Approval Process About?

Prior approval is a streamlined process where your council checks that your larger extension meets permitted development rules and assesses its impact on neighbours. Here’s how it works:

The Application Process

You submit drawings and pay a fee (currently around £240). The council then writes to your immediate neighbours giving them 21 days to comment.

If No Objections

Assuming your extension meets all the technical rules, the council must grant prior approval. This typically takes 6-8 weeks total.

If There Are Objections

The council assesses the impact on neighbouring properties and makes a decision on whether to approve or refuse. You can appeal refusals, but it adds time and uncertainty.

The key advantage is that if no one objects and you meet the rules, approval is virtually guaranteed. It’s much more predictable than full planning permission.

Do These Rights Apply to My Property Type?

This is crucial – permitted development rights mainly apply to houses, not flats or maisonettes. If you live in a converted house or a purpose-built flat, you almost certainly can’t use these rights for extensions.

Properties That Can Use Permitted Development:

  • Detached houses
  • Semi-detached houses
  • Terraced houses
  • End-of-terrace houses

Properties That Usually Can’t:

  • Flats and maisonettes
  • Houses converted into flats
  • Commercial buildings
  • Mixed-use properties

Even if you have a house, your rights might be restricted or removed entirely in certain areas or circumstances.

When Don’t These Rights Apply to My Area?

Several factors can restrict or remove your permitted development rights:

Conservation Areas

Many permitted development rights are restricted in conservation areas. You typically can’t build side extensions or use certain materials without planning permission.

Listed Buildings

Listed buildings have very limited permitted development rights. Most changes require both planning permission and listed building consent.

Article 4 Directions

Local councils can remove permitted development rights in specific areas through Article 4 directions, often used to protect particular neighbourhoods.

National Parks and AONBs

Areas of Outstanding Natural Beauty, National Parks, and World Heritage Sites have additional restrictions on permitted development.

Always check with your local council whether any of these restrictions apply to your property before assuming you can use permitted development rights.

What About Building Regulations – Do I Still Need Them?

Yes, absolutely. This is where many people get confused. Permitted development rights only deal with planning permission – you still need building regulations approval for most extension work.

Building regulations cover structural safety, insulation, fire safety, drainage, and accessibility. Even if your extension doesn’t need planning permission, it almost certainly needs building regulations approval.

The good news is that building regulations are usually more straightforward than planning permission. It’s about meeting technical standards rather than subjective planning policies.

How Much Space Can My Extensions Cover Overall?

There’s a crucial rule that catches many people out: all your extensions and outbuildings combined can’t cover more than 50% of your property’s land area (excluding the original house footprint).

This includes previous extensions, sheds, garages, conservatories – everything counts towards this limit. If you’re already close to 50% coverage, you might not be able to extend further under permitted development.

What Materials Can I Use for My Extension?

Your extension must use materials that are “similar in appearance” to your existing house. This doesn’t mean identical, but they should look sympathetic to the original building.

For example, if your house is red brick, you can’t suddenly use yellow brick or timber cladding without planning permission. Similarly, if your house has a pitched tile roof, a flat roof extension might need planning permission.

This rule is often overlooked but can invalidate your permitted development rights if ignored.

Can I Add Windows Wherever I Want?

No, there are specific rules about windows, especially on side elevations. Any windows on the side of your extension (facing neighbours) must be:

  • Obscure glazed (frosted glass)
  • Non-opening, OR
  • If they do open, the opening parts must be at least 1.7 metres above floor level

This prevents overlooking your neighbours’ gardens and maintains their privacy.

What Happens If I Get It Wrong?

If you build thinking you have permitted development rights but actually exceed the rules, you’re in breach of planning control. The council can serve an enforcement notice requiring you to demolish or alter the work.

The safest approach is to apply for a Lawful Development Certificate before starting work. This costs around £103 and gives you written confirmation that your project qualifies as permitted development.

Why Don’t More People Know About These Rights?

Many homeowners and even some builders don’t fully understand permitted development rights. This leads to expensive and unnecessary planning applications, or worse, building work that breaches planning rules.

The rules are complex and change periodically. What was true five years ago might not be true today. Professional advice is often worth the investment to avoid costly mistakes.

How Do I Know If My Project Qualifies?

The best approach is to have your project assessed by someone who understands the rules properly. The government’s technical guidance runs to over 60 pages of detailed rules and exceptions.

Key things to check:

  • Your property type and location
  • Exact measurements from the original house
  • Previous extensions and outbuildings
  • Local restrictions like conservation areas
  • Height limits and boundary distances
  • Materials and design requirements

Getting this wrong can be expensive, so professional advice often pays for itself.

What’s Changed in 2025?

The main permitted development rights remain largely unchanged in 2025, but there have been some updates to make the system clearer and more accessible. The larger home extension scheme is now permanent, having been extended indefinitely after its pandemic introduction.

There’s also increased focus on energy efficiency and sustainable building materials within permitted development, reflecting the government’s net-zero commitments.

Should I Use Permitted Development or Apply for Planning Permission?

This depends on your specific situation. Permitted development is great when:

  • Your project clearly fits within the rules
  • You want certainty and speed
  • You want to avoid planning fees and delays
  • Your neighbours are unlikely to object

Planning permission might be better when:

  • Your project exceeds permitted development limits
  • You’re in a conservation area or other restricted zone
  • You want maximum design flexibility
  • Your project is complex or unusual

Making the Most of Your Rights

Understanding permitted development rights can save you thousands of pounds and months of waiting. But the rules are complex and the penalties for getting them wrong are severe.

At Rosebrick Developments, we’ve been helping families across Nottinghamshire, South Yorkshire, and Derbyshire navigate these rules since 2014. As an experienced Mansfield builder, we know exactly what works in our local area, what doesn’t, and how to maximise your permitted development rights whilst staying within the law.

Our design and build service includes checking your permitted development entitlements, handling any prior approval applications, and ensuring your project complies with building regulations. We take the complexity out of the process so you can focus on enjoying your new space.

Whether you’re planning a simple extension or exploring the larger home extension scheme, we’ll give you honest advice about what’s possible and help you make the most of your rights.

Ready to explore your permitted development options in Nottinghamshire, South Yorkshire, or Derbyshire? Contact Rosebrick Developments today for expert advice on making the most of your rights.