Do You Need a Party Wall Agreement?

General guidance for homeowners in England and Wales. Last reviewed: 12 September 2026

General information, not a decision on any specific property. For a specific proposal, a party wall surveyor can confirm what applies. See our AI Disclaimer.

A separate process from planning permission

The Party Wall etc. Act 1996 is a distinct piece of legislation from planning permission and Building Regulations. It is not decided by your local planning authority, and having planning permission (or not needing it) has no bearing on whether the Party Wall Act applies. It exists to manage your legal relationship with a neighbour where work affects a shared or adjacent structure — separately from whether the council is satisfied with the proposal.

What kind of work is typically covered

• Work directly to a party wall — a wall shared with a neighbouring property, including cutting into it, raising it, underpinning it, or inserting a damp-proof course.
• Building a new wall at or astride the boundary — with a neighbouring owner, where the new wall sits on or against the line separating the two properties.
• Excavation near a neighbouring building — digging foundations or other excavations within specified distances and depths of a neighbour's building or structure, where the work may affect its support.

Whether a specific proposal is notifiable depends on its exact position, depth and relationship to the boundary and neighbouring structures — this needs to be assessed for the actual work proposed, not assumed from the general project type.

What serving notice involves

Where the Act applies, the property owner carrying out the work must serve formal written notice on affected neighbours before starting, describing the proposed work and giving a set notice period. A neighbour can consent, or can dissent — in which case a party wall surveyor (or surveyors, one for each side, or an agreed surveyor) is appointed to prepare a "party wall award" setting out how and when the work can proceed, and recording the condition of the neighbouring property beforehand.

Why this matters even with planning permission and Building Regs sorted

It's possible to have full planning permission and Building Regulations approval and still be in breach of the Party Wall Act if notifiable work starts without proper notice. The two processes run on separate tracks with separate consequences — a planning or Building Control decision does not satisfy Party Wall Act requirements, and vice versa.

What this means in practice

If your project involves work on or near a boundary, checking the Party Wall Act position early — alongside, not instead of, planning and Building Regulations — avoids delays later. A party wall surveyor can confirm whether your specific proposal is notifiable and manage the notice process.

See also: ArchLens for homeowners & developers, Rear extension planning permission and Loft conversion planning permission.