Party Wall Agreements Explained

When notice is required

Broadly, notice is needed for work directly to a shared wall, for building on the boundary line, and for excavation within defined distances of a neighbouring building where you dig deeper than their foundations.

Cutting into a shared wall to take a beam bearing · Removing a chimney breast on a party wall · Raising or underpinning a shared wall · Building a new wall on or at the boundary · Excavating close to a neighbour's structure below their foundation level

Notice periods

Different types of work carry different statutory notice periods, and they run from service of the notice rather than from when work is planned. That is why notices are prepared alongside the drawings, not once a contractor is booked.

A neighbour can consent in writing, in which case matters proceed. If they dissent, or do not respond within the response period, a dispute is deemed and surveyors are appointed to produce an award.

The schedule of condition

A schedule of condition records the state of the neighbouring property before work starts, usually with photographs. It protects both sides: it prevents pre-existing cracks being attributed to your build, and it gives your neighbour clear evidence if genuine damage occurs.

Even where a neighbour consents and no award is needed, a photographic record before starting is worth the hour it takes.

Practical advice

Speak to the neighbour before the formal notice arrives. A legal document landing unannounced is the most common reason a straightforward consent turns into a dissent and an appointed-surveyor process.

Party wall procedure is separate from planning permission and building regulations. Having permission does not remove the obligation, and neither does having a very cooperative neighbour — the procedure exists to protect both parties if something goes wrong later.

Frequently asked questions

Can a neighbour stop my extension with a party wall notice?

No. Dissent does not block the work; it triggers the surveyor process that sets out how the work is carried out and how any damage is dealt with.

Who pays for party wall surveyors?

The party carrying out the work normally bears the reasonable costs, since the work is for their benefit.

What if my neighbour ignores the notice?

If they do not respond within the statutory period, a dispute is deemed to have arisen and the process moves to surveyor appointment.

Do I need a party wall notice for a garden room?

Generally not, unless you are excavating close to a neighbouring structure below their foundations or building on the boundary line itself. A lightweight base near a boundary usually falls outside it, but the distances and depths are worth checking.