Do I need planning permission, or is my project permitted development?
What permitted development actually is, the five things that remove it, and why the honest answer always ends at the council rather than at a checklist.
- Difficulty
- beginner
- Time
- 30 min
- Read
- 4 min
- Safety
- caution
Short answer
Permitted development is a national grant of planning permission for certain house alterations, subject to conditions. You have it unless something has taken it away — a flat, a listed building, a designated area, an Article 4 direction, a condition on the original permission, or an allowance already used up by earlier work. Work through those, then confirm with the council.
Permitted development is not an exemption from planning law. It is planning permission already granted by legislation, on conditions, and the conditions are precise. That is why the sensible way to approach the question is backwards: rather than asking whether your project fits, ask what could remove the right altogether, because those tests are quick and they settle most cases.
Safety
Step by step
- Check whether the property has permitted development rights at all.Flats and maisonettes do not have the householder rights that houses do for extensions and outbuildings. Houses converted from something else, and buildings in mixed use, can also sit outside them.
- Check for listing and designation.A listed building needs listed building consent for work affecting its character, inside and out, and permitted development is heavily curtailed. Conservation areas, National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites all restrict what is permitted, particularly at the side and to the roof.
- Check for an Article 4 direction.A local planning authority can remove specified permitted development rights across an area by direction — commonly for windows, doors, roofs, front boundaries and hard surfacing in older residential areas. Your council's planning pages list its directions.
- Check the original planning permission for the house.New-build estates very often have permitted development rights removed by a planning condition. Search the council's planning register for the address, open the original decision notice, and read the conditions. This single check catches a large share of surprises.
- Check what has already been built.Permitted development allowances are cumulative and run with the property, not with the owner. An extension or outbuilding added by a previous owner has already consumed part of the allowance, and the original house means the house as first built, not as you bought it.
- Then check the conditions of the specific class.Each type of work has its own limits on height, depth, position relative to the original house and to boundaries, roof form, materials and whether it faces a highway. The Planning Portal sets out the current conditions for England and Wales; Scotland and Northern Ireland publish their own.
- Treat any single failed condition as fatal.Permitted development is all-or-nothing for that class. Exceeding one limit by a small margin does not make the project mostly permitted — it makes the whole thing development requiring permission.
- Ask the council, in writing, and keep the answer.Many councils offer a pre-application or duty-planner service. An officer's view is worth having before you spend money on drawings, but it is an opinion and it does not bind the council.
- Apply for a lawful development certificate if the answer matters.It is a formal determination, on the record, and it is what a buyer's solicitor asks for. On anything that alters the building, this is the step that turns a belief into a document.
Tips
- Measure from the original house as first built, not from the back of the conservatory somebody added in 1998. This is the most common measuring error there is.
- Corner plots are treated differently, because a side elevation facing a road can be caught by rules aimed at frontages.
- Permitted development for larger single-storey rear extensions in England runs through a prior approval process where the council notifies neighbours. That is a procedure, not an exemption, and it has to be completed before work starts.
Common mistakes
- Relying on a neighbour who did the same thing — Their property may not share your designations, conditions or extension history, and their work may itself be unauthorised and simply not yet challenged.
- Reading an article without checking which nation it applies to — Permitted development classes in England, Scotland, Wales and Northern Ireland are genuinely different. An England answer applied in Scotland can be flatly wrong.
If it doesn't work
The council's website is unclear about whether an Article 4 applies
Cause: Directions are often mapped rather than listed by address — Fix: Ring the planning duty line with the address, and ask specifically which permitted development rights are restricted at that property. Ask for it by email so you have it in writing.
You cannot tell what the original house looked like
Cause: Several rounds of previous work — Fix: Search the planning register for the address, and look at historic mapping and aerial imagery. A planning consultant can establish the original footprint where it genuinely matters.
Questions people ask
Is permitted development the same as not needing planning permission?
In effect yes, but only because permission has already been granted nationally on conditions. Break any condition and the work is unauthorised development, not a minor technicality.
How do I prove my project was permitted development?
Apply to the council for a lawful development certificate. It is decided on the plans you submit, it is a formal determination rather than an opinion, and it is the document conveyancing solicitors ask for.
Do permitted development rights apply to flats?
The householder rights for extensions and outbuildings do not apply to flats and maisonettes. Assume you need permission and check with the council, and check the lease as well.