Do you need planning permission or building regulations for roof work?

Planning permission asks whether the work may be built at all: how it looks from the street, how large it is, whether the building is protected. Building Regulations ask whether the finished work is safe, weathertight and energy efficient. A job can need one without the other, and a yes from one door tells you nothing about the other. Ask both questions early, because the answers can change the order of work, the materials and the timing of a quote.

The checking itself is done either by a team inside the council or by a private firm on the Building Safety Regulator's register of building control approvers, a register that opened under regulations in force from 6 April 2024. Which council team you deal with depends on the address, because shared services cross district boundaries.

Folkestone & Hythe building control is on 01303 853538. The East Sussex Building Control Partnership, which serves Rother along with Eastbourne, Hastings and Wealden, is on 01892 602005. Either team can tell you whether your plan needs an application, and it is worth asking before a contractor is booked, so the answer can shape the quote.

Part L of the Building Regulations covers energy. The edition in force for dwellings in England is Approved Document L, 2021 edition, which took effect on 15 June 2022. A 2026 edition takes effect on 24 March 2027 for most work, so until then the 2021 figures apply.

Two tables matter for roofs. Table 4.2 covers new elements in an existing home, and Table 4.3 covers elements that are renovated or retained.

The U-value figures are in W/(m²·K). The renovation rule has a trigger. The whole roof is brought up to the 0.16 column if more than 50% of its surface is renovated, or if the job is a major renovation, meaning more than 25% of the surface area of the external building envelope is renovated. Renewing the waterproof layer of a flat roof is classed as renovation.

The standard gives way where it has to. If 0.16 is out of reach on technical or practical grounds, or a simple payback would take longer than 15 years, the roof is brought to the lowest U-value that works in practice and repays itself within 15 years. For a roof window, the window figure applies and the rooflight one does not.

Dormers fall under Class B, the enlargement of a dwellinghouse by an addition or alteration to its roof. The volume limits are 40 cubic metres for a terrace house and 50 cubic metres in any other case, and nothing may extend beyond a slope that forms the principal elevation and fronts a highway. Class B does not apply at all on article 2(3) land: conservation areas, National Landscapes (the Kent Downs and the High Weald are two) and World Heritage Sites such as the Canterbury one. Class C has no such exclusion, so plain re-roofing is not caught by it. In a National Landscape the district council still decides applications, and the landscape team only advises.

A listed home keeps its permitted development rights for roof work, but it also needs listed building consent wherever the work changes the building's character. Churches follow their own routes. A Church of England church still in use is dealt with by faculty. Unitarian and Quaker meeting places, and redundant churches, need listed building consent if they are listed.