Do you need permission for a new flat roof in a conservation area?

Planning law starts from a simple test. Section 55(2)(a) of the 1990 Act carves out alterations that leave the exterior of a building visibly unaltered, and those are not development. Only development needs planning permission. A new membrane laid over the same deck, at the same height, with the same edges and the same outline, usually passes. From the pavement nothing looks different, so there is nothing for a planning officer to object to.

Living in a conservation area does not switch that test off, but it does make people look harder at anything visible from public places. Plenty of flat roofs hide behind a parapet or sit at the back of an extension, where the question hardly arises. Where yours can be seen from the road, the safe habit is to describe the plan to the council in a short email and ask whether it agrees that the work is like for like. Keep the reply with your paperwork.

Change is the trigger. Raising the roof level, adding or lifting a parapet, building up an edge so it stands proud, swapping a lead or zinc finish for a shiny modern one, or replacing a pitched roof with a flat one can all alter how a building reads from outside. Any of those can bring an application into the picture, and in a conservation area the council weighs them against the look of the street.

Rooflights and lanterns are a separate matter. A new opening in a flat roof is an addition, not a re-covering, and the permitted development rules for roof alterations carry their own limits, which our answer on planning permission for a skylight sets out. Flats are different again. A flat, or a building containing flats, is not a dwellinghouse under the General Permitted Development Order, so the householder rights do not apply and the council is your starting point for anything beyond like-for-like.

Two things can take away the easy answer. The first is an Article 4 direction, a council's way of taking certain permitted development rights away inside a mapped area. Arun's directions remove no roof rights. The direction covering the Craigweil House conservation area in Aldwick deals with verges and front-garden hard surfaces, and the houses in multiple occupation direction concerns change of use. For an address in Chichester District, ask the council's planning team which directions apply to your street.

The second is listing. Alterations affecting the special interest of a listed building need listed building consent, and that reaches a flat roof on a listed extension, porch or outbuilding. Ordinary maintenance and like-for-like repair is treated more gently, but the council decides what counts as ordinary. If your home is listed, ring the council's conservation team before you agree a price with anyone. Our page on re-roofing a listed building covers that route.

For most of Bognor Regis the local planning authority is Arun District Council. The Steyne and Waterloo Square conservation area dates from August 1979 and was extended in July 1994, and the Aldwick Road conservation area followed in July 1994. For either, Arun's conservation team can say how a flat roof reads from the street, and whether yours is seen at all.

Addresses inside the South Downs National Park follow a different path. Where the Park falls within Arun, Horsham, Adur or Worthing, the National Park Authority itself takes the decision. Where it falls within Chichester or East Hampshire, the district council receives and processes the application for the Authority. Harbour-side homes may also sit in Chichester Harbour National Landscape, renamed in 2023 from its earlier designation as an Area of Outstanding Natural Beauty. Whichever applies, put the address and what you plan to do in your first message, so you get one clear answer rather than a referral.

Planning is about looks. Building Regulations are about performance, and they apply in a conservation area just as they do anywhere else. Under Approved Document L, laying a fresh membrane across a flat roof is renovation, so insulation may become part of the job, as we explain in our answer on insulating a flat roof when you replace it.

At survey we photograph the existing roof, tell you whether we think the work is like for like, and the price comes as a single written total. If the council asks for a drawing or a note of materials, we help you describe them in plain terms. Our flat roofing page covers the work itself, and the Building Regulations guide for flat roofs walks through falls, insulation and approval. A conservation area adds a conversation to the job, and only rarely a different roof. Ask the question early, keep the reply, and the rest of the project runs as it would anywhere else in Bognor.