Knowledge base
Does a pergola count towards the 50% garden rule?
How the England outbuilding coverage limit works and what else must be included in the calculation.
If the council treats a pergola as an outbuilding in England, include its covered ground area when checking the permitted development coverage limit. Planning Portal says additions and other buildings must not cover more than half the land around the original house.
Start with the land around the original house, not simply the garden visible today. Planning Portal defines the original house as the house when first built or as it stood on 1 July 1948 if built before then. An extension put up by a previous owner may therefore reduce the area available for later development even though it felt like part of the house when you bought it.
Then add the footprints of the relevant existing additions and buildings. Do not calculate the pergola as 50% of the remaining lawn. The test is about the total covered area against the land around the original house. The official page also says decking and raised platforms are included among the additions considered for the limit.
A title plan, old planning records and measured site plan can help when the house has changed over time. If the original footprint or the status of an older structure is unclear, ask the council rather than relying on a rough online map. Planning Portal describes its page as introductory guidance and warns that local restrictions can also apply.
Wales and Scotland use their own wording and areas for similar permitted development tests. Use the national guidance for the property's location.
Sources
- Planning Portal: outbuildings — accessed 14 November 2026.
- GOV.WALES: planning permission for outbuildings — accessed 14 November 2026.
- mygov.scot: sheds, garages and similar buildings — accessed 14 November 2026.
Read does a pergola need planning permission? and the glossary entries for original house and outbuilding.