Planning permission
Do you need planning permission for rooflights or skylights?
- Covers
- rooflight, skylight, roof window, conservation rooflight, roof lantern
- The law
- GPDO 2015, Schedule 2, Part 1, Class C, paragraphs C.1 and C.2
- Applies to
- England
Short answer
Not usually, for a house in England. Rooflights are "any other alteration to the roof" under Class C of Part 1 of the General Permitted Development Order 2015. They are permitted development if they project no more than 0.15 metres beyond the plane of the original roof slope and are no higher than the highest part of the original roof. A rooflight in a side roof slope must be obscure-glazed and non-opening below 1.7 metres above the floor.
Unlike dormers, rooflights are not excluded on Article 2(3) land, so they can be permitted development in a conservation area unless an Article 4 direction removes the right. A listed building needs listed building consent.
Check your own project Check your address
Development is not permitted by Class C if ... the alteration would protrude more than 0.15 metres beyond the plane of the slope of the original roof when measured from the perpendicular with the external surface of the original roof
The limits
| Rule | Limit | Order |
|---|---|---|
| Projection | 0.15 m, measured at right angles to the original roof surface | C.1(b) |
| Height | No higher than the highest part of the original roof | C.1(c) |
| Side roof slopes | Obscure-glazed, and non-opening unless the opening part is more than 1.7 m above the floor | C.2 |
| Not covered | Chimneys, flues, soil and vent pipes, solar panels | C.1(d) |
Original roof, not existing roof
Class C measures against the original roof: the roof as built, or as it stood on 1 July 1948 if older. The technical guidance points out that this differs from Class B, which measures height against the existing roof. The Planning Portal's summary of Class C refers to the existing roof; the Order says original. On a roof that has already been raised or extended, the difference matters.
Where the roof of a new Class A extension joins the original roof, the technical guidance says the 0.15 metre limit does not apply to that join. A rooflight or lantern in the roof of a new extension is part of the extension, and the technical guidance measures an extension's height at its highest part, which can include things standing above the roof. A roof lantern that stands more than 0.15 metres above the flat roof of the original house is outside Class C.
Solar panels are not covered by Class C; see solar panels. Rooflights in a loft conversion that also has a dormer are still assessed under Class C, and the dormer under Class B.
Conservation areas and listed buildings
Class C has no exclusion for Article 2(3) land, which includes conservation areas, National Landscapes, National Parks, the Broads and World Heritage Sites. A rooflight on the front slope of a house in a conservation area can therefore be permitted development, provided the council has not withdrawn Class C rights with an Article 4 direction. A rooflight on a listed building needs listed building consent if it would affect the building's character (section 7 of the Planning (Listed Buildings and Conservation Areas) Act 1990).
Building Regulations
The Planning Portal says a new rooflight will generally need Building Regulations approval: the rafters or joists are cut and trimmed, the roof must carry the load, the rooflight must meet energy efficiency limits, and fire performance matters near a boundary. A replacement rooflight in an existing home can be self-certified by an installer registered with a competent person scheme (Building Regulations 2010, Schedule 3, paragraph 10).
What this means for you
Check the projection of the product you have chosen, measured at right angles to the roof, and confirm that no Article 4 direction covers your street. The permitted development checker asks both questions.
Getting certainty
If you need written confirmation, for example for a rooflight on the front slope in a conservation area, a lawful development certificate for proposed works gives it. From 1 April 2026 the fee for householder works is £274, and the council has 8 weeks to decide.
Sources
- GPDO 2015, Schedule 2, Part 1, Class C legislation.gov.uk
- Permitted development rights for householders: technical guidance, September 2019 gov.uk
- Planning Portal: roof, planning permission planningportal.co.uk
- Planning Portal: rooflights, Building Regulations planningportal.co.uk
- Building Regulations 2010, Schedule 3 legislation.gov.uk