Permitted Development
In plain English: Building work you can do on a UK home without a full planning permission application, subject to specific size, height and material limits. Covers many loft conversions, single-storey rear extensions and garage conversions in England — but is removed in conservation areas, listed buildings and Article 4 directions.
Permitted development (often abbreviated PD) is building work on a UK home that doesn't need a full planning permission application. Instead the government has granted permission in advance, subject to specific size, height, material and other limits. Permitted development covers many of the home improvements that homeowners most commonly want to do — including loft conversions, single-storey rear extensions, and garage conversions.
What's commonly permitted development in England
- Rear dormers up to 40 m³ on terraces, 50 m³ on semis and detached, subject to materials matching and no front-facing work.
- Single-storey rear extensions up to 3 m (semi/terrace) or 4 m (detached) from the original rear wall; extended via prior approval to 6 m / 8 m.
- Garage conversions where the structure isn't expanded.
- Small outbuildings in the garden, subject to area and height limits.
- Porches under 3 m² floor area and 3 m high.
- Internal alterations that don't change the building's external appearance.
When permitted development doesn't apply
- Conservation areas, especially under an Article 4 direction.
- Listed buildings — every alteration needs listed-building consent regardless of size.
- Flats — most PD rights are for dwellinghouses, not flats.
- Above PD limits — extensions exceeding 3 m / 4 m, or dormers exceeding the volume limit, need full planning permission.
- Material change of use — converting an outbuilding to a self-contained dwelling needs planning permission.
Where Offrly fits
Many of the highest-£-per-£ home improvements Offrly's Scenario Explorer lets you model — loft conversions, rear extensions, garage conversions — fall under permitted development for most UK homes outside conservation areas. Check with your local planning authority before committing.
Read the umbrella guide on UK home improvement value for the picture across all five Scenario Explorer levers.
Indicative market guidance — not a regulated valuation and not financial, tax or legal advice. For mortgage, insurance, probate or tax purposes, consult a RICS-qualified surveyor and an independent qualified adviser. For specific planning advice, consult a chartered town planner or your local planning authority.
Related terms
- Planning permission — what you need when work exceeds permitted-development limits
- Conservation area — Article 4 directions in conservation areas remove most PD rights
- Listed building — listed buildings have no PD rights — every alteration needs listed-building consent
FAQ: Permitted Development
What is permitted development in the UK?
Permitted development is building work on a UK home that doesn't need a full planning permission application — instead the government has granted permission in advance, subject to size, height, material and other limits. Permitted development covers many loft conversions (rear dormers under volume limits), single-storey rear extensions (under depth and height limits), garage conversions where the structure isn't expanded, and a range of smaller alterations like outbuildings and porches.
What are the permitted development limits for a rear extension in England?
Single-storey rear extensions in England can extend up to 3 m from the original rear wall on terraced and semi-detached houses, or 4 m on detached houses, under standard permitted development. The 'larger home extension' prior-approval process extends these to 6 m and 8 m respectively. Maximum height is 4 m, eaves height matches the original. Different limits apply to extensions on side elevations or above ground floor.
What's an Article 4 direction?
An Article 4 direction is a local planning authority's removal of permitted development rights for a specific area or building type — most often used in conservation areas to require planning permission for alterations that would normally be permitted development (changing windows, painting frontages, small extensions). Check with the local planning authority before assuming permitted development applies.
Do permitted development rights apply to flats?
Largely no. Most permitted development rights in England apply to dwellinghouses, not flats. Internal alterations and some specific extensions on the top floor of a block of flats may be permitted, but the standard rear-extension and loft-conversion PD rights do not apply to flats. Always check with the local planning authority.