Neither a planning approval nor a building regulations approval replaces that process. [1]
Identify the wall and the boundary
Establish whether the proposal concerns an existing party wall, a wall wholly on one owner's land, or a new wall at the line separating the properties. They are not interchangeable. The government's explanatory booklet distinguishes party walls from external walls and boundary walls belonging wholly to one owner. [1]
Where the boundary's location is disputed, resolve that issue separately. A party wall award cannot determine the legal boundary. Obtain legal advice where the title or ownership position is uncertain before the design depends on a particular wall line. [1]
A new wall up to the boundary
Building a wall wholly on your land but up to the boundary can require a line-of-junction notice. The normal notice period is one month. A neighbour's silence in response to this type of notice does not have the same consequence as silence following a notice for work to an existing party wall. [1]
The drawings should identify the wall position and foundation arrangement. The Act contains particular provisions for necessary projecting foundations; special foundations under neighbouring land require written consent. Do not assume that every foundation projection is allowed or that every type follows the same consent rule. [1]
A new wall astride the boundary
There is no right to build a new party wall astride the boundary without the adjoining owner's written consent. If that consent is not given within the relevant procedure, the new wall must instead be wholly on your land. A friendly discussion, shared builder or planning permission is not a substitute for written agreement. [1]
Record the location, agreed construction and allocation of costs clearly. For a coordinated project with your neighbour, also settle what happens if one part of the project is delayed or cancelled.
Raising an existing party wall
The Act provides rights for certain work to an existing party wall, including raising it and cutting into it for a beam bearing. This is normally subject to a party structure notice with a two-month notice period. If consent is not given, the dispute-resolution procedure may be required; lack of consent is not necessarily an absolute veto on qualifying work. [1]
The wall's structural adequacy remains a separate question. An engineer should assess the existing construction and the loads introduced by the addition. Where foundations are close to a boundary, an offset or other engineered arrangement may be necessary rather than an assumed standard detail. [2] [3]
Check the whole construction detail
Planning-height limits, fire resistance, rainwater arrangements and the building's structural design must all be resolved alongside the wall procedure. Building near a boundary does not remove the building regulations requirements for fire spread and appropriate construction. [4] [5]
Agree access and protective measures before starting. Any statutory access right is limited to qualifying work and its procedure, not a general permission to use the neighbour's garden throughout the build. [1]