What permitted development means
Permitted development rights (PD or PDR) are a national grant of planning permission for certain types of minor works, set out in the General Permitted Development Order. If your project falls cleanly within the limits, you can build it without applying for planning permission — the permission already exists in law.
That's the appeal, and also the trap: PD rights come with detailed size, height, position and use limits, and a long list of conditions and exceptions that can quietly take them away.
Common projects covered by permitted development
- Rear extensions — single-storey extensions within set depth, height and eaves limits
- Loft conversions — including rear dormers, within volume allowances
- Outbuildings — garden offices, sheds and garages within coverage and height rules
- Porches — within small footprint and height limits
- Change of use — e.g. certain commercial-to-residential conversions under specific classes
- Solar panels and EV charging points — usually permitted within limits (more in our solar & EV planning data guide)
The catch: when permitted development doesn't apply
This is where most people come unstuck. PD rights are restricted or removed entirely in many situations:
- Designated areas — conservation areas, National Parks, AONBs and World Heritage Sites have tighter limits
- Listed buildings — PD rights are heavily curtailed, and listed building consent is a separate requirement
- Flats and maisonettes — most householder PD rights apply only to houses, not flats
- Article 4 directions — a council can formally withdraw specific PD rights in a defined area (see below)
- Conditions on a previous permission — earlier planning permissions sometimes remove PD rights as a condition
Article 4 directions
An Article 4 direction is how a local authority switches off a permitted development right in a particular location — common in conservation areas to control things like replacement windows, or in areas where the council wants to limit commercial-to-residential conversions. If an Article 4 direction applies, work that would normally be permitted development does need a planning application. Always check whether one is in force before relying on PD.
Prior approval: permitted, but not automatic
Some permitted development is only allowed if you first get prior approval — the council doesn't decide the principle (that's already granted), but it does check specific matters like flooding, highways, contamination or design. Larger rear extensions and many change-of-use conversions work this way. It's faster and more certain than a full application, but it's not "do nothing." Our dedicated guide on prior approval walks through the process and timescales.
Why you still want a Lawful Development Certificate
Even when work is genuinely permitted development, it's worth applying for a Lawful Development Certificate (LDC). It's the council formally confirming, in writing, that your project is lawful and didn't need permission. When you come to sell, a buyer's solicitor will ask how you know the extension was permitted — an LDC answers that cleanly and protects the property's value. Without it, "we were told it was permitted development" is not the same as proof.
How to check permitted development activity in your area
Prior-approval notifications and Lawful Development Certificates are recorded in the planning system just like full applications — they show up as their own application types. That makes them a useful signal: you can see what neighbours have done under PD, gauge how a council treats borderline cases, and confirm whether prior approvals in an area are typically granted or refused.
curl "https://api.planwire.io/v1/applications\ ?postcode_prefix=BS8\ &type=Prior%20Approval\ &date_from=2025-06-01" \ -H "X-API-Key: your_api_key"
For architects, developers and proptech tools, pulling this programmatically across an area shows the real-world pattern of what's being permitted — far more useful than guessing from the regulations alone.
Rule of thumb: permitted development saves time, but always confirm the property isn't a flat, listed, in a designated area, or subject to an Article 4 direction before you build. When in doubt, an LDC is cheap certainty.
The bottom line
Permitted development is one of the most useful — and most misunderstood — parts of the planning system. The principle is simple: certain minor works are pre-approved. The reality is a web of limits and exceptions where the same extension is permitted on one street and needs a full application on the next. Check the constraints, use prior approval where required, and document everything with an LDC.