What is a party wall agreement and when do I need one?

Full answer

The Party Wall etc. Act 1996 governs building work that affects a wall shared with a neighbour (a party wall), an adjoining structure, or excavation near a neighbour's building. It is a procedural framework designed to prevent and resolve disputes, not a tax or planning matter -- it sits alongside planning permission and building regulations rather than replacing them. You must serve written notice on adjoining owners before starting qualifying works. Typical examples include cutting into a party wall to insert a beam (common in loft conversions and through-lounge knock-throughs), demolishing and rebuilding a party wall, building a new wall on or up to the boundary line, or excavating within three or six metres of a neighbour's building below the depth of their foundations. Notice periods are generally two months for works to the party wall itself and one month for boundary or excavation works. If the neighbour consents in writing, you can proceed. If they dissent or do not respond, a dispute is deemed to arise and surveyors are appointed -- either one agreed surveyor or one each -- to draw up a party wall award. The award records the condition of the neighbouring property beforehand (a schedule of condition), specifies how and when work proceeds, and allocates costs. The building owner usually pays the surveyors' fees. Who it affects: homeowners doing extensions, loft or basement conversions, or any work touching a shared or boundary wall in England and Wales (the Act does not apply in Scotland). There are no statutory fees set in legislation -- surveyors' fees vary by job, so this card cannot quote a figure; obtain quotes. Failing to follow the process can let a neighbour seek an injunction halting your works, so serve notice early. Budget the cost as part of your project; use a mortgage or stamp-duty calculator when planning the overall finances of a renovation or purchase.

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