You live in a conservation area and you want to improve your home. Maybe you're looking at a rear extension to open up the kitchen, or a loft conversion to add a bedroom. You've heard that conservation areas have stricter rules - and you're wondering whether you can do anything at all without a planning application.
The answer is: more than you think, but less than you'd have outside one. Conservation areas reduce your permitted development rights - but they don't eliminate them. Single storey rear extensions, outbuildings, and some types of alteration are still PD. Roof extensions, side extensions, and changes to external cladding are not.
Conservation areas are classified as "article 2(3) land" in the GPDO - the same category as National Parks, AONBs, World Heritage Sites, and the Broads. The restrictions apply equally to all designated land. Here's what you can and can't do.
Rear extensions are still PD in conservation areas. Roof extensions are not. That's the key distinction.
A single storey rear extension within the standard depth limits is still permitted development in a conservation area. The same measurement rules apply - depth from the original rear wall, 4-metre maximum height, eaves capped at 3 metres within 2 metres of a boundary. Materials must match the existing house.
The prior approval route for larger extensions (up to 8m detached, 6m semi/terrace) is also available in conservation areas. This requires notifying the council and a 42-day consultation. The fee is £249.
Two storey rear extensions are not permitted development on designated land. If you want to extend at first floor level in a conservation area, you need planning permission (£548). For full extension rules, see our extensions guide.
This is the big one. On designated land, Class B rights are completely removed. Any addition or alteration to the roof that enlarges the house - a dormer, a hip-to-gable conversion, raising the ridge height - requires planning permission.
However, rooflights on the rear roof slope are usually still permitted under Class C, which has separate (and less restrictive) rules for designated land. Front-facing rooflights on designated land do need permission. A rooflight-only loft conversion - adding windows and a staircase without changing the roof structure - may not need planning permission at all, as no enlargement is involved. For full details, see our loft conversion guide.
Not sure whether your property is in a conservation area? The free eligibility check uses postcode data to identify designated areas automatically.
Outbuildings are still PD in conservation areas, with one additional restriction. On designated land, any outbuilding positioned more than 20 metres from any wall of the house is limited to 10 square metres of ground coverage. Closer than 20 metres, the standard Class E rules apply in full.
On most urban plots, the garden isn't long enough for this to matter - the entire garden is within 20 metres of the house. It mainly affects larger properties with deep gardens or grounds. For full outbuilding rules, see our shed and outbuilding guide.
Some councils go further than the standard designated area restrictions by making Article 4 directions in specific conservation areas. These can remove PD rights that would otherwise still apply - such as changing windows, replacing front doors, altering boundary walls, or even painting the exterior of the building.
Not all conservation areas have Article 4 directions, and those that do may only cover specific streets or specific types of work. You need to check with your council whether an Article 4 direction applies to your property on top of the standard conservation area restrictions.
Common mistakes that cost money
Assuming you can't do anything. Many homeowners in conservation areas assume all PD rights are removed. They're not. Single storey rear extensions, outbuildings, and rear rooflights are all still PD in most cases.
Assuming the rules are the same as outside a conservation area. They're not. Roof extensions, side extensions, two storey extensions, and cladding changes all need planning permission.
Not checking for Article 4 directions. Standard conservation area restrictions are automatic. Article 4 directions are additional and council-specific. Both can apply to the same property.
Confusing conservation area rules with listed building rules. A conservation area protects the character of an area. A listing protects a specific building. Your house can be in a conservation area without being listed - and the rules are different.
PD Assessment Tool
Our free eligibility check automatically identifies whether your property is in a conservation area, National Park, AONB, or other designated area using postcode data. If your property qualifies for PD, the full assessment checks every condition for your project type - with designated area restrictions built in.
Free eligibility check. Full assessment £47.
Content verified against the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended), article 2(3) designated land provisions, and Classes A, B, C, and E of Part 1, Schedule 2 (legislation.gov.uk, revised version). Government's technical guidance (September 2019). SI 2026/313 confirmed no changes to these provisions. This page is for general information only and does not constitute legal advice.
April 2026