Are Party Wall Agreements Compulsory?

Serving a party wall notice is legally required for certain types of building works under the Party Wall etc. Act 1996. Whether a full formal agreement (or award) then becomes compulsory depends on your neighbour's response. But skipping the notice stage entirely is never a safe option — the consequences can be significant.

The Short Answer

Party wall notices are compulsory whenever your proposed works fall under the Act. A full party wall agreement (award) only becomes compulsory if your neighbour dissents or fails to respond. If they consent in writing, no formal award is needed.

Which Works Trigger a Compulsory Notice?

You must serve a notice for any of the following:

Section 3 — Party Wall Works

• Cutting into a party wall (e.g. for a new RSJ steel beam)
• Raising the height of a party wall
• Demolishing and rebuilding a party wall
• Underpinning or consolidating a party wall's foundations
• Removing a chimney breast on a party wall

Section 6 — Excavation near Neighbouring Foundations

• Excavating within 3 metres of an adjoining building to a depth below its foundations
• Excavating within 6 metres if the excavation would undercut a 45-degree line from the base of the neighbour's foundations

Section 1 — New Boundary Walls

• Building a new wall astride (straddling) the legal boundary
• Building a new wall up to or immediately adjacent to the boundary

What Happens If You Skip the Notice?

There is no automatic criminal penalty for failing to serve a notice. However, the civil consequences can be severe:

• Injunction — Your neighbour can apply to court and a judge can order you to stop work immediately, even if the foundation is already half-dug.
• Unlimited liability for damage — Without an award and schedule of condition, you lose important legal protections. Any damage — whether clearly caused by your works or not — is much harder to dispute.
• Costly retrospective process — Some solicitors and surveyors will attempt to carry out a retrospective award, but not all surveyors are willing to do this, and it provides weaker protection.
• Strained neighbour relations — Works proceeding without notice are a common cause of long-running neighbour disputes.

Is There Any Way to Start Without a Notice?

Technically, nothing physically stops you from starting work without serving a notice — but you take on significant legal and financial risk. The Act does not have inspectors who visit sites. Enforcement is driven by the adjoining owner applying to court.

For routine works where the neighbour is friendly and clearly supportive, some building owners take this risk. However, relationships change during construction, and what starts as a friendly verbal agreement can deteriorate when dust, noise, or unexpected damage appear.

Are There Any Exemptions?

Yes. Works that are entirely internal and do not affect the shared wall are not notifiable. Common examples:

• Installing a new kitchen or bathroom entirely within your property
• Internal non-structural partitions
• Redecorating
• Replacing windows on your own property (unless this involves work to the party wall)
• An extension that does not come close to any neighbouring foundation

If you are unsure whether your works are notifiable, serve a notice anyway. There is no penalty for serving an unnecessary notice, but there are real risks for omitting one that should have been served.

Does Permitted Development Change Anything?

No. Permitted development rights relate to planning law — what you are allowed to build without needing planning permission. They have no bearing on the Party Wall Act. You can have full permitted development rights for a rear extension and still be legally required to serve a party wall notice for excavation near the boundary.

Serving Your Own Notice

The notice itself is not legally complex. It must contain specific information required by the Act, but you do not need a solicitor or surveyor to draft or serve it. Use our notice generator to produce a correct, professional notice and serve it yourself for £89. If your neighbour consents, that covers your full compliance cost.