Planning permission for roof work
Re-roofing and adding flush rooflights are usually permitted development, but altering the shape of the roof, dormers, raising the ridge, needs permission.
Maintaining or replacing a roof rarely needs permission. The line is crossed when you change the roof’s shape or add elements that materially change how it looks from the street.
- Re-roofing and repairs that do not materially change the appearance
- Rooflights that project no more than 150mm above the roof slope
- Alterations that do not exceed the height of the existing roof
- Side-facing roof windows that are obscure-glazed and 1.7m+ above the floor
- Dormers and roof extensions on the principal elevation, or that raise the ridge
- Loft conversions and upward extensions (separate, tighter rules)
- Homes in conservation areas and other designated land, and any flat
- Changing the roof material or form where rights have been removed
Don't forget building regs
Re-roofing that replaces more than a quarter of the roof area triggers building regulations, mainly for thermal upgrade and, sometimes, structural checks on the extra weight of new coverings. We can prepare the details and calculations.
If your project is really a loft conversion or you are changing the roof line, we design it and confirm the planning route. For structural questions about a new covering or opening, our engineers can help. Browse roof ideas for inspiration.
Frequently asked
Do I need planning permission to replace my roof?
Usually not, if you are re-roofing without materially changing the appearance or exceeding the existing roof height. Changing to a very different material, or altering the shape, can need permission, especially in a conservation area.
Do I need permission to add rooflights?
Flush rooflights that project no more than 150mm above the slope and do not rise above the ridge are normally permitted development. Rooflights on a principal elevation in a conservation area are the main exception.
Not sure where your project stands?
Checking whether you need planning permission is one of the first things we do: on the house, before any drawings. Tell us about your project and we'll confirm the route.