What This Requirement Covers
Permitted development rights allow certain types of building work to be carried out without the need to apply for planning permission. These rights are set out in the Town and Country Planning (General Permitted Development) (England) Order 2015 (GPDO). However, Building Regulations still apply to most permitted development work.
Key Requirements
Single-Storey Rear Extensions
- Maximum depth: 3 metres (attached houses) or 4 metres (detached houses) under normal permitted development
- Prior approval (larger home extension scheme): Up to 6 metres (attached) or 8 metres (detached), subject to neighbour notification and prior approval from the local authority
- Maximum eaves height: 3 metres
- Maximum overall height: 4 metres
- Width must not exceed the width of the original house
- Must not extend beyond the rear wall of the original house on the side nearest to a boundary by more than 50% of the width of the original house
Two-Storey Rear Extensions
- Maximum depth: 3 metres from the original rear wall
- Must be at least 7 metres from the rear boundary
- Maximum eaves height must match the existing house eaves height
- Not permitted within 2 metres of a side boundary
Loft Conversions
- Maximum additional roof space: 40 m³ (terraced houses) or 50 m³ (detached and semi-detached)
- Dormers must not extend beyond the plane of the existing roof slope on the principal elevation
- Materials must be similar in appearance to the existing house
- No verandas, balconies, or raised platforms
- Side-facing windows must be obscure-glazed and non-opening below 1.7 metres
Outbuildings
- Must be single storey with a maximum eaves height of 2.5 metres
- Maximum overall height: 4 metres (dual pitch) or 3 metres (any other roof)
- Must not cover more than 50% of the garden area
- Must not be forward of the principal elevation
- No sleeping accommodation in outbuildings within the curtilage of a listed building
Restrictions
Permitted development rights may be restricted or removed
- In conservation areas, national parks, Areas of Outstanding Natural Beauty, and the Broads
- On listed buildings (both the building and its curtilage)
- Where an Article 4 direction has been made by the local authority
- Where previous extensions or alterations have used up the permitted development allowances
- On flats (most permitted development rights apply only to houses)
Important: Building Regulations Still Apply
- Even where planning permission is not required, Building Regulations approval is required for most building work
- A building notice or full plans application must be submitted to Building Control
- Structural work, drainage, fire safety, and energy efficiency must all comply with the Building Regulations
Practical Compliance Tips
- Always check whether your property has full permitted development rights; conservation areas, listed buildings, and Article 4 directions restrict or remove them
- Apply for a Lawful Development Certificate if there is any doubt about whether the work is permitted development; this provides formal confirmation
- Remember that permitted development applies to planning only; Building Regulations are a separate requirement
- Measure extensions from the original house (as built or as it existed on 1 July 1948, whichever is later), not from any existing extension
- Check the cumulative impact of previous extensions and outbuildings; permitted development rights have overall limits
- For the larger home extension scheme, the neighbour notification process takes 42 days; factor this into the project programme
- Keep records of all permitted development work for property sales