Planning
Party walls and garden projects: when the Party Wall Act applies
If you build on a shared boundary wall, or dig foundations close to a neighbour's building, the Party Wall Act may require formal notice to your neighbour first.
In short
The Party Wall etc. Act 1996 can apply to garden work that affects a shared structure or a neighbour's foundations. It is most relevant when you build on or into a wall that is shared on the boundary, when you take down and rebuild such a wall, or when you excavate for foundations within 3 metres of a neighbour's building and below its foundation level. Where it applies, you must serve formal notice on the affected neighbour before starting, and either agree the work or appoint surveyors. It is separate from planning permission and from the rules on how high a garden wall can be.
The thresholds
Where the line sits
The Party Wall etc. Act 1996 is the law most people have never heard of until a neighbour mentions it, and it catches more garden work than you would expect. It is separate from planning, and it deals with works that affect a shared structure or a neighbour's building. In a gard
| Situation | Party Wall Act |
|---|---|
| Building on an existing shared boundary wall | Notice usually required |
| Taking down and rebuilding a party wall | Notice usually required |
| Excavating within 3 metres of a neighbour building, below its foundations | Notice usually required |
| A new wall wholly on your own land | Usually not, but the boundary still matters |
Source: Gardenscape. Figures as of 2026-06-01.
Yes, no, or it depends
Scenarios in plain language
No, they are separate. A wall can be permitted development for planning and still need a party wall notice if it affects a shared structure or a neighbour's foundations.
Usually not, if it is wholly on your own land and does not affect a shared structure or excavate near a neighbour's building. We confirm at the design stage.
Not if it is handled early. The point of serving notice in good time is to agree the work and avoid a dispute or a hold-up later.
The local layer
Designated land and Article 4
The Party Wall etc. Act 1996 is the law most people have never heard of until a neighbour mentions it, and it catches more garden work than you would expect. It is separate from planning, and it deals with works that affect a shared structure or a neighbour's building. In a garden context the common triggers are building on or into a wall that sits on the boundary and is shared, taking down and rebuilding such a wall, and digging foundations within 3 metres of a neighbour's building where you go below the level of their foundations, which can come up with a substantial retaining wall, a garde
A note
General guidance, not advice. Rules vary by site, and Article 4 directions or conditions can change what applies. Check with your local authority and the Planning Portal.
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