What are permitted development rights?
Permitted development (PD) rights are planning permissions granted by the Town and Country Planning (General Permitted Development) (England) Order 2015 (GPDO 2015) that allow certain building works and changes of use without a full planning application. For landlords, the most commercially significant PD rights cover dwellinghouse extensions, C3 to C4 HMO conversions, and commercial to residential conversions under Class MA.
Dwellinghouse extensions (Part 1, Class A)
- Single-storey rear extension: up to 3m from original rear wall (semi or terraced); 4m (detached). Larger Home Extension scheme extends to 6m/8m subject to prior approval
- Two-storey rear extension: up to 3m from original rear wall, minimum 7m from rear boundary
- Loft conversions: up to 40m� (terraced) or 50m� (detached/semi) of additional roof space
- Maximum height: 4m at the eaves for single-storey extensions; no higher than original roof ridge
- Not applicable to: listed buildings, flats, conservation areas (many works require prior approval)
C3 to C4 � HMO conversion without planning permission
Converting a C3 family home to a C4 small HMO (3�6 unrelated occupants) is permitted development in England unless the local planning authority has made an Article 4 Direction removing this right. HMOs with 7 or more occupants are sui generis � a full planning application is always required. Article 4 Directions affecting HMO conversions are widespread in university towns including Oxford, Cambridge, Nottingham, Bristol, Leeds, and many others. Check your local authority's planning map.
Class MA � commercial to residential conversion
Class MA allows certain Class E commercial buildings (offices, retail, cafes, light industrial) to be converted to dwellinghouses under a prior approval process. Requirements: the building must have been in Class E use for at least 2 continuous years and vacant for at least 3 months before application. Prior approval is required � the council has 56 days to decide on defined grounds. Many councils, particularly in London and city centres, have removed Class MA rights with Article 4 Directions.
When PD rights do not apply
- Listed buildings: any works require listed building consent � PD rights do not apply
- Conservation areas: many extension works require prior approval or full planning permission
- Flats: Part 1 extension rights do not apply to flats or maisonettes
- Sui generis HMOs (7+ occupants): always require a full planning application
- Areas with Article 4 Directions: the specific PD rights removed by the direction require a full planning application
Lawful Development Certificate
If there is doubt about whether proposed works are within PD rights, apply to the local planning authority for a Lawful Development Certificate (LDC). An LDC provides legal certainty and is particularly important if you plan to sell or remortgage the property. LDC applications typically cost �100�200 and are decided within 8 weeks. A certificate of lawful existing use (CLEU) can confirm that a C4 use established before an Article 4 Direction is lawfully continuing.
This guide is accurate as at 27 May 2026. It is provided for information purposes only and does not constitute legal advice.