With apologies to Pink Floyd, this article will discuss the increasingly vexed issue of the construction of mega-basements in Central London and the way in which the Party Wall etc. Act 1996 (the ‘Act’) is being used, tactically, to oppose those large-scale projects.

The first question that a would-be developer or ‘building owner’ should consider is whether the project they have in mind involves ‘notifiable work’ for the purposes of the Act. Unsurprisingly, notice must be served under the Act on the owner of any adjoining property (the ‘adjoining owner’) if the building work will interfere with a ‘party structure’. Broadly speaking, that term means any physical structure that is shared by two buildings, or which straddles the boundary between two adjoining pieces of land.

You might think the Act does not apply to the construction of a basement. The nature of the construction work involved is very different from say, building a loft conversion, where there is an obvious risk of damage to any shared walls. However, Section 6 of
the Act provides that notice must also be served on the adjoining owner no less than 14 days before the commencement of excavation work less than 6 metres from the foundations of his property. That should be close enough for most basement projects.

Needing to engage the Act is no bad thing, however. If the parties are unable to agree terms between themselves then Section 10 sets out a clear mechanism for dealing with disputes. Expert surveyors are appointed to agree the terms of a party wall award, which, amongst other things, avoids the costs that could otherwise result from the adjoining owner bringing a claim against the building owner for nuisance and/or trespass.