Does a party wall notice apply?

The Party Wall etc. Act is not optional and not a formality. If you are building on, into or near a shared wall or boundary, or excavating near a neighbour's foundations, your neighbour is entitled to notice — usually two months before work starts.

There are three broad triggers: work directly to a shared wall, building a new wall at the boundary line, and excavating within three or six metres of a neighbouring structure below the level of its foundations. Most rear extensions and almost all basements engage at least one.

Notices are served on owners, including freeholders and leaseholders. Neighbours can consent in writing, or dissent — which means surveyors are appointed and an award is prepared.

A homeowner served no notice because the neighbour had said it was fine over the fence. Three days into excavation, unhappy with the noise, the neighbour obtained an injunction. Work stopped for five weeks and the eventual legal and surveyor costs ran to five figures — for a notice that costs nothing to serve.

Consent, if you get it, must be in writing. That protects both of you.

Before work starts, a dated photographic record of the neighbour's property records existing cracks and defects. Homeowners think of it as a courtesy to the neighbour. It is at least as much protection for you, because it is the only reliable defence against a claim for damage that was already there.

A formal notice arriving unannounced reads as hostile. A short conversation first — what you are doing, roughly when, that a legal notice is coming because the law requires it — turns the paperwork into procedure rather than provocation. Timing is on your side; two months of goodwill is worth buying.