The Party Wall etc. Act 1996

What the Act covers

The Act is structured around three situations. Section 1 deals with building at the line of junction where no wall currently exists. Section 2 deals with works on or to an existing party wall or party structure. Section 6 deals with excavations close to neighbouring buildings.

What counts as notifiable works

The following are typical examples of works that trigger the Act. It is not an exhaustive list, and every site needs to be checked against the lease plan, the survey, and the proposed drawings.

• Cutting into a party wall to take the bearing of a beam, commonly for a loft conversion.
• Inserting a damp proof course all the way through a party wall.
• Raising, thickening or underpinning a party wall.
• Demolishing and rebuilding a party wall.
• Building a new wall astride or up to the line of junction between two properties.
• Excavating within three metres of a neighbouring structure where the new foundations go deeper than the neighbour's.
• Excavating within six metres where the excavation cuts a 45-degree line drawn down from the base of the neighbour's foundations.

For a focused guide on the excavation trigger, see the section 6 guide and the 3 metre rule.

The party wall process in outline

The Act is procedural. Each step exists for a reason, and skipping one usually invalidates the rest. The basic sequence is:

• Identify whether the proposed works are notifiable under the Act by reference to sections 1, 2 and 6.
• Serve notice on every adjoining owner, giving the correct statutory period before works start.
• Wait for the adjoining owner's written response. Silence for 14 days is treated as dissent.
• If the neighbour consents in writing, keep the consent on file and proceed.
• If the neighbour dissents or does not respond, a dispute has arisen and surveyors must be appointed.
• The appointed surveyor or surveyors produce a Party Wall Award governing how the works are carried out.

For the detail of the notice itself, see the party wall notice guide. For the award that closes the process, see party wall award.

The role of the surveyor

A party wall surveyor is a statutory appointment under the Act. Once appointed, the surveyor is not acting as an advocate for the appointing owner. The role is to act impartially to resolve the dispute and produce an Award that is fair to both sides.

The parties can either appoint one Agreed Surveyor between them, or each appoint their own surveyor, with a Third Surveyor selected to resolve disagreements. See the party wall surveyor cost guide for how the fee structure typically works, and the London surveyor guide for the practical considerations around dense city sites.

What happens if the Act is ignored

The Act does not contain criminal sanctions, but the civil consequences of ignoring it are real and frequently expensive:

• Adjoining owners can apply for an injunction to stop works that began without a valid notice or award.
• An injunction is available as a remedy where the Act has been ignored, though seeking one carries procedural risk and cost for the party applying.
• Retrospective appointments are possible but awkward, and usually cost more than doing things properly in the first place.
• Damage claims become harder to defend without an Award and a record of condition to compare against.
• Relations with neighbours deteriorate, which frequently adds cost and delay to projects that could have been straightforward.

Common mistakes

• Assuming that planning permission or building control approval removes the need for a party wall notice. It does not.
• Serving informal emails or text messages rather than a correctly drafted statutory notice.
• Running the statutory period from the wrong date, which invalidates the notice.
• Treating silence from a neighbour as consent rather than as a deemed dispute.