The Party Wall etc Act 1996 applies across England and Wales. It can apply to your extension or loft if the work touches a shared wall, builds on the boundary, or excavates close to a neighbour's building. It's separate from planning permission and Building Regulations, so having those doesn't remove your duty to give notice.
Three Common Triggers
| Work | Example | Minimum notice |
|---|---|---|
| Work to an existing party wall | Cutting in a steel beam on a semi or terrace | 2 months |
| A new wall on the boundary line | An extension wall built at the boundary | 1 month |
| Excavating near a neighbour's building | Foundations close to next door | 1 month |
Work can start sooner only if your neighbour agrees in writing. They don't have to. A notice lapses if work hasn't started within 12 months, so don't serve it too early.
What Happens After You Serve Notice
- Your neighbour agrees in writing. Keep a record, and consider a schedule of condition with photos of their side.
- Your neighbour dissents, or doesn't reply within 14 days. For most notices, this is treated as a dispute.
- Surveyors are appointed. You can use one agreed surveyor, or one each. They issue an award setting out how the work will proceed.
Who Arranges and Pays?
You, as the person doing the work, must give the notice. GOV.UK publishes an explanatory booklet and example letters. Surveyor costs are decided under the award, and the building owner commonly pays where the work is solely for their benefit.
How This Fits With Ashbridge
Party wall surveyor services aren't included in our design packages. Our drawings and structural calculations show what's proposed at the shared wall, which is the information a surveyor will need. For anything beyond that, speak to a party wall surveyor.
Build the time into your programme: with a two-month notice, you need to start this well before your builder's start date.
A general guide, not legal advice. Take advice from a party wall surveyor or solicitor for your own project.