Permitted development rules in 2026: what’s actually law right now, what’s still just a proposal, and when you need full planning permission regardless.
Permitted development rules have not changed in 2026. The limits in force today, for extension depth, height, and loft conversion volume, are the same ones set in 2019. A bill to extend them is working through the House of Lords, and a government consultation on similar changes closed back in April 2024, but neither has become law. If a headline told you otherwise, it is describing a proposal, not a rule you can build under.
That distinction matters. Design or apply for planning on the assumption that wider permitted development limits already exist, and you can end up with unauthorised works, a rejected lawful development certificate, or a scramble to submit a full planning application partway through a project.
In this article
- Have permitted development rules actually changed in 2026?
- What’s on the table, and why it isn’t law yet
- What you can build under permitted development right now
- When you still need full planning permission, proposal or not
- What’s an Article 4 direction, and could it affect you?
- Should you get a Lawful Development Certificate anyway?
- Frequently asked questions
Have permitted development rules actually changed in 2026?
No. Every limit you can currently build to under permitted development rights, the 3 to 8 metre rear extension depths, the 40 to 50 cubic metre loft conversion allowances, the eaves and ridge height caps, has been in place since the last major update in 2019. The HomeOwners Alliance confirms the government has “not yet made any final decisions” on the changes currently being discussed.
What has happened in 2026 is a wave of blog posts and guides using “2026” in the title while describing a bill that has not passed. It is easy to read past the small print and assume the bigger numbers are already usable. They are not, not yet.
What’s on the table, and why it isn’t law yet
Two separate efforts are behind the confusion.
The Permitted Development Rights (Extension) Bill, a Private Member’s Bill introduced in the House of Lords by Lord Lucas in September 2024, proposes larger rear extension depths, removal of some curtilage restrictions, and permitted development rights for bungalows. As of the most recent update on the bill’s own tracking page, it has passed its first and second readings and is now in committee stage in the Lords. It has not reached the House of Commons, and a Private Member’s Bill without government backing rarely becomes law in its original form. Check the bill’s page directly for the current stage before relying on it.
Separately, a government consultation covering similar ground closed in April 2024. No formal government response had been published as of the most recent reporting. Until one is, the consultation has no legal effect either.
Put together: real proposals, genuine parliamentary time, no change to what you can actually build.
What you can build under permitted development right now
These are the limits actually in force, for a typical house without an Article 4 direction, listing, or conservation area restriction.
| Project | Limit under permitted development |
|---|---|
| Single storey rear extension, terraced or semi-detached | 3m standard, up to 6m with prior approval |
| Single storey rear extension, detached | 4m standard, up to 8m with prior approval |
| Extension height | Under 4m (3m if within 2m of a boundary) |
| Two storey rear or side extension | Max 3m depth, must not cover more than 50% of the original garden, matching materials and roofline |
| Loft conversion, detached or semi-detached | Up to 50 cubic metres of added roof space |
| Loft conversion, terraced | Up to 40 cubic metres of added roof space |
Figures per the HomeOwners Alliance permitted development guide, current as of 2026. Always confirm against your own property and local authority before design work starts.
We check permitted development eligibility, Article 4 restrictions, and planning history before we draw a single line, so your design is buildable from the first sketch.
Book a planning assessment →When you still need full planning permission, proposal or not
Even under the current, unchanged rules, permitted development does not cover every property or every project. Full planning permission is required for:
- Flats and maisonettes, which have no permitted development rights for extensions
- Listed buildings, and most work within their curtilage
- Homes in conservation areas, where side extensions and roof alterations are typically restricted
- Properties covered by an Article 4 direction removing specific permitted development rights
- Leasehold properties, unless the freeholder has given consent
- Extensions or conversions that exceed the size, height, or coverage limits above
What’s an Article 4 direction, and could it affect you?
An Article 4 direction is a local authority order that removes some permitted development rights in a specific area, usually to protect the character of a conservation area or a street of similar houses. Several London boroughs have them, including parts of Hillingdon. Where a direction applies, work that would normally be permitted development anywhere else needs a full planning application instead.
Article 4 directions are usually specific to a defined area or road, not a whole borough, so a two minute check against your local authority’s planning policy map before you commission drawings can save weeks later.
Should you get a Lawful Development Certificate anyway?
A Lawful Development Certificate (LDC) is optional for permitted development work, but it is the document that proves, on paper, that your extension or loft conversion was lawful at the time it was built. Councils typically take a couple of months to issue one.
It matters most at resale. A conveyancing solicitor or buyer’s surveyor who spots an extension with no planning history and no LDC will usually ask for one before exchange, which is a far worse time to discover a measurement was 200mm over the limit than during design.
From lawful development certificates to full planning applications and building control submissions, we manage the paperwork so the project keeps moving.
See planning services →Frequently asked questions
Is it true that permitted development limits got bigger in 2026?
No. The limits are unchanged since 2019. A House of Lords bill proposes bigger limits and is in committee stage, and a related government consultation has had no formal response. Neither has legal effect yet.
How many cubic metres can a loft conversion add without planning permission?
Up to 50 cubic metres for a detached or semi-detached house, and up to 40 cubic metres for a terraced house, under current permitted development rules.
What happens if the Permitted Development Rights (Extension) Bill becomes law?
Rear extension depths, curtilage restrictions, and possibly bungalow eligibility could widen. Until it completes report stage and third reading in the Lords, passes the Commons, and receives royal assent, none of that applies. Check the bill’s official tracking page for its current stage before designing around it.
Does permitted development apply to flats?
No. Flats and maisonettes have no permitted development rights for extensions or loft conversions. Any such work needs full planning permission.
How do I check if my property has an Article 4 direction?
Search your local council’s planning policy pages for “Article 4 direction” and check the accompanying map against your address, or ask an experienced professional to check as part of a pre-application review.
We’ll check what your property can actually build under current rules, Article 4 restrictions included, before drawings start.
Book a consultation →Related reading: How Long Does an Extension Really Take?