Party walls separate buildings owned by different owners, so if you live in a semi-detached or terraced house you would be sharing a wall or walls with your neighbours and this is called the party wall as it is used by both parties.

• The excavation of foundations within 6m of an adjoining structure and below a line drawn at 45 deg from the bottom of its  foundations.
• The Excavation of foundations within 3m of an adjoining structure which would be lower than its foundations.
• The insertion of a beam into a shared wall.
• The insertion of a damp proof course all the way through a shared wall.
• The demolition and rebuilding of a party wall.
• Underpinning any parts of the party wall.
• The raising of the whole of the party wall including cutting off any object that may prevent this from happening.
• Cutting a flashing into an adjoining building to protect adjoining walls.
• The building of a new wall on the line of junction (boundary) between two properties.
• …… and a number of other issues relating to building works near neighbouring properties of different owners.

The Act is basically a dispute resolution procedural process, for building works that occur beside neighbouring buildings and/or structures.

It is normal for the Building Owner who instigates the works to pay for all costs (expenses & fees) under the  “ Act  “.