The Party Wall etc. Act 1996 is the piece of legislation that governs building works affecting a shared boundary in England and Wales. It exists to let owners carry out legitimate works to their own property while protecting the neighbour next door from damage, disruption, or nasty surprises.
In practice, it covers the walls, floors and boundary structures you share with an adjoining owner — plus any excavation deep enough to affect their foundations. Before those works start, a formal notice has to be served and, if the neighbour dissents, a surveyor's Award sets out exactly what can be done, when, and who pays for what.
The Act applies across England and Wales to any works on or near a shared structure — most commonly the wall between semi-detached or terraced homes, garden boundary walls built astride the line, and excavations within three or six metres of a neighbouring building. It sets out who must be notified, how much notice is required (two months for works to the wall itself, one month for excavations), and the procedure for resolving disagreements without recourse to the courts.
For a fuller walk-through — what counts as party wall work, how the process feels from both sides, and the pitfalls we see most often — read the full guide on our blog.