Permitted Development Rights for London Houses: Complete Guide 2025

Permitted Development (PD) rights allow homeowners in England to carry out certain types of work without needing to apply for planning permission. For London homeowners, understanding what falls within PD and what requires a planning application is the starting point for any extension, conversion, or alteration project. This guide summarises the main PD rights for London houses in 2025.

PD rights apply to dwelling houses (not flats or maisonettes, which have no permitted development rights for extensions or loft conversions). They are subject to conditions and limitations, and they may be restricted or removed in conservation areas, Article 4 direction areas, listed building curtilages, Areas of Outstanding Natural Beauty, and National Parks. PD rights can also be restricted by conditions attached to the original planning permission for the property — always check the original consent.

Rear extensions under Class A of the GPDO: A single-storey rear extension up to four metres height may be built without a planning application if it extends no more than three metres beyond the rear wall of the original house for semi-detached or terraced properties, or six metres for a detached house. Extensions between three and six metres (semi/terraced) or six and eight metres (detached) may be built under the prior approval (neighbour consultation) scheme rather than a full planning application. Double-storey rear extensions are also possible under PD within specific height, eaves, and setback limits. The extension must be constructed in materials that are similar in appearance to the existing house.

Loft conversions under Class B of the GPDO: Additional roof space may be created by altering the shape of the roof without a planning application, subject to volume limits (40 cubic metres additional roof space for a terraced house, 50 cubic metres for a semi-detached or detached house), height limits (not exceeding the existing roof ridge), and other conditions including that any dormer must not protrude forward of the principal elevation.

Outbuildings under Class E of the GPDO: Outbuildings (garden offices, sheds, studios, pools, and similar) may be built within certain limits — single storey, under four metres height (two and a half metres if within two metres of a boundary), not forward of the principal elevation, covering less than fifty percent of the curtilage (excluding the original house footprint). Outbuildings must not be used as a separate dwelling.

Porches under Class D: A small porch (maximum area three square metres, not exceeding three metres height, not less than two metres from the highway boundary) may be added without planning permission.

Changed use: Converting a garage, outbuilding, or office space to residential use within the curtilage of the main house falls within PD subject to conditions.

All PD works are subject to Building Regulations compliance regardless of whether planning permission is needed. For extensions and loft conversions, a Building Regulations application is always required.

For certainty, homeowners can apply for a Lawful Development Certificate from the local authority to confirm that proposed or completed work is lawful under PD. This is not a planning application — it is a certificate confirming the legal status of the work. It typically costs around two hundred and five pounds and takes eight weeks.

RCB advises on PD rights and planning status as part of our pre-construction service for London projects. +44 7359 872594 | connect@rcbGroup.co.uk | www.rcbGroup.co.uk