This is general guidance based on standard permitted development rights in England. Rules differ for listed buildings, conservation areas, and properties with Article 4 directions. Always confirm with your local planning authority before starting work.
Do I Need Planning Permission for a General Outbuilding?
Any detached building within the grounds of your home used for purposes incidental to the dwelling, such as storage, a workshop, a gym, or a games room. This covers the general outbuilding rules under the GPDO.
The General Position
This project is usually allowed under permitted development rights without needing to apply for planning permission, provided certain conditions and limits are met.
Generally permitted under Part 1, Class E of the GPDO. Outbuildings must be for purposes incidental to the enjoyment of the dwelling and must comply with height, position, and area limits.
Conditions and Requirements
- 1Must be for purposes incidental to the enjoyment of the dwelling
- 2Must not be forward of the principal elevation fronting a highway
- 3Maximum height 2.5m if within 2m of a boundary
- 4Maximum height 4m (dual-pitch roof) or 3m (any other roof) if more than 2m from a boundary
- 5Must not cover more than half the curtilage (all outbuildings and extensions combined)
Size and Dimension Limits
- Height within 2m of boundary: 2.5m maximum
- Height elsewhere: 4m (dual pitch) or 3m (other roofs)
- No single footprint limit, but cumulative total must not exceed 50% of curtilage
When Permitted Development Does Not Apply
- In designated areas, outbuildings to the side of the house are not PD
- In designated areas, total outbuilding area exceeding 10 square metres requires PP
- Must not be used as sleeping accommodation or a separate dwelling
- Total cumulative outbuilding footprint (including sheds, summer houses, etc.) counts towards the 50% limit
What About Building Regulations?
Under 15 square metres with no sleeping accommodation: normally exempt. Between 15 and 30 square metres: must be at least 1m from any boundary or constructed of substantially non-combustible materials. Over 30 square metres: Building Regulations apply in full.
Building regulations are separate from planning permission. You may need both, one, or neither depending on your project. Building regulations cover the safety and quality of building work, including structural integrity, fire safety, insulation, ventilation, and drainage.
How to Apply for Planning Permission
Check if you need permission
Review the permitted development rules above. If in doubt, contact your council or apply for a Lawful Development Certificate.
Prepare your application
You will need scaled drawings, a site plan, and a completed application form. An architect or planning consultant can help with this.
Submit to your local council
Applications can be submitted online via the Planning Portal or directly to your council. Select your council below for a direct link.
Wait for a decision
8 weeks for householder planning applications if PP is needed..
Application cost: £258.
What Happens If I Build Without Permission?
Enforcement risk increases with the size and use of the outbuilding. Large outbuildings that dominate the garden or are used for residential or commercial purposes attract enforcement. Neighbours' complaints are a common trigger for council investigation.
Find a Builder for Your General Outbuilding
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Select Your Council
Choose your local council for guidance specific to your area, including links to apply and whether your council has conservation areas or Article 4 directions that could affect your project.
London
South East
South West
East of England
East Midlands
West Midlands
North East
North West
Yorkshire and the Humber
CA = has conservation areas. A4 = has Article 4 directions. These may restrict your permitted development rights.