Guide · 12 October 2026

Party walls: a short guide for London homeowners

Most London houses share at least one wall with a neighbour, so the Party Wall etc. Act 1996 comes up on almost every extension and loft.

When it applies

• Work directly on a shared wall, such as cutting in steel beams or raising the wall.
• Building a new wall on or at the boundary line.
• Digging foundations close to a neighbour's building, within the distances set out in the Act.

Notice periods

GOV.UK guidance says you must give notice at least two months before work on a party wall, and at least one month before building on the boundary line or excavating near a neighbour's foundations.

What happens next

Your neighbour can agree in writing, or dissent. If they dissent, surveyors draw up a party wall award describing how the work will be done. Talking to neighbours early, before notices go out, often makes the whole process smoother.

Source: GOV.UK – Party Wall etc. Act 1996: guidance. This is general information, not legal advice.