Permitted Development Rules: What You Can Build Without Planning Permission

Understanding Permitted Development rights can save you thousands of pounds and months of waiting that a full planning application would involve. In 2026, PD rights remain one of the most valuable tools available to UK homeowners — but the rules are nuanced, and getting them wrong can lead to enforcement action or problems when you sell. This complete guide covers everything you need to know.

What Is Permitted Development?

Permitted Development rights are a set of national planning rules, set out in the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended). They grant planning permission automatically for certain types of development, as long as specific criteria are met — meaning you don't need to submit a formal planning application to your local authority.

The rules exist because Parliament recognised that many routine home improvements are unlikely to harm the local environment or neighbours, and shouldn't need the full planning process. However, PD rights are not unlimited — they come with conditions on size, height, materials and location.

It's important to understand the distinction between PD rights and Building Regulations. Just because something is permitted under PD doesn't mean Building Regs don't apply. In most cases they do — see our Building Regulations guide for more.

Key Permitted Development Allowances

Rear Extensions (Single-Storey)

Single-storey rear extensions are allowed under PD up to:

• 4m depth for detached houses (up to 8m with Prior Approval)
• 3m depth for semi-detached and terraced houses (up to 6m with Prior Approval)
• Maximum 4m height at the ridge
• Maximum 3m at the eaves if the extension is within 2m of a boundary

For a detailed breakdown of what this means in practice, see our guide: do you need planning permission for a single-storey extension?

Loft Conversions

Loft conversions under PD are allowed subject to volume limits:

• 50m³ additional roof space for detached and semi-detached houses
• 40m³ for terraced houses
• No extension beyond the plane of the existing roof slope on the principal elevation
• Dormers to the rear are generally allowed, but must not exceed the highest part of the roof
• No balconies on loft conversions under PD

Curious about costs? Our guide covers loft conversion costs in the UK in full detail.

Outbuildings

Garden offices, sheds, garages and other outbuildings fall under Class E of the PD order. Key rules:

• Maximum height: 4m (dual-pitched roof) or 3m (any other roof)
• Within 2m of a boundary: maximum 2.5m height
• Must not be in front of the principal elevation
• Must not cover more than 50% of the land around the original house (including other extensions and outbuildings)
• Not for use as a separate dwelling (no sleeping or living independently)

Porches

Adding a porch to your front door is allowed under PD, provided:

• Ground area does not exceed 3m²
• Maximum height 3m
• Not within 2m of any boundary with a highway

Solar Panels

Installing solar panels on the roof of a house or outbuilding is generally permitted under PD, provided panels do not protrude more than 200mm beyond the roof plane and do not exceed the highest point of the roof. Ground-mounted solar requires permission only if over 9m² in area.

Fences, Walls and Gates

You can erect fences, walls and gates under PD up to:

• 2m high elsewhere in the garden
• 1m high next to a road or footpath

What Is NOT Covered by Permitted Development Rights

PD rights do not apply to:

• Flats and maisonettes — no PD rights for extensions or loft conversions
• Listed buildings — all works require Listed Building Consent
• Balconies or raised platforms on extensions
• Two-storey extensions within 7m of the rear boundary
• Cladding the outside of a house with stone, timber, plastic or tiles in a designated area
• New dwellings in the garden (separate houses) — always need PP
• Anything that would bring the total covered area of extensions + outbuildings above 50% of the garden

Article 4 Directions

Local planning authorities can restrict or remove PD rights in specific areas using an Article 4 Direction. These are particularly common in:

• Conservation areas
• National Parks and Areas of Outstanding Natural Beauty (AONBs)
• World Heritage Sites
• Some high-density residential areas where the council wants to protect the character of the street

Always check with your local planning authority whether an Article 4 Direction applies to your property before assuming PD rights are available. You can usually find this information on the council's planning portal or by calling the planning department directly.

Certificate of Lawful Development

Even if your project clearly falls within PD, it's strongly advisable to apply for a Certificate of Lawful Development (CLD) from your local planning authority. A CLD is a formal legal document confirming that your development was or is lawful.

Benefits of getting a CLD:

• Provides certainty — protects against future enforcement action
• Essential when selling — solicitors will ask for evidence that works were lawful
• Faster and cheaper than a full planning application (typically £103 fee in England)
• Application can be made after the work is complete (retrospective)

Common Projects: Permitted Development Status

If you're planning a loft conversion and want cost estimates, see our loft conversion cost guide. For extension costs, our single-storey extension cost guide has full price breakdowns.

Frequently Asked Questions