Building works to a boundary wall or involving works close to a boundary often fall under the ‘Party Wall Act’.
This 1996 Act is legislation which aims to prevent or resolve disputes between neighbours concerning work done to boundary walls and nearby buildings.
The Act sets out the procedure when one neighbour wants to carry out repairs and alterations to a boundary wall that is considered a "party wall" . It can apply to both walls and other structures that may be on the boundary or close to it. It applies not just to garden walls but to works to floors in flats and loft conversions in semi detached houses. It covers both the steps that you must take before undertaking works and your rights if a neighbour wants to undertake works, and what each party's rights are in the event of a dispute.
An example of a dispute could be where a neighbour withholds their consent to you carrying out works to a boundary wall or structure.. The Act sets out the steps you must take to resolve the dispute and be able to lawfully undertake the works.
There are strict procedures and timetables to be followed and it can be a complicated area of law. If you are undertaking works to a boundary structure that is covered by the Act it may be best to seek legal advice before starting work especially if you know there could be difficulties ahead.