Excavation near neighbours — the 3m & 6m rules explained
To undertake your building work you may need to excavate near your neighbours. It might be for new foundations, a basement or for other reasons, even excavating for a new drainage pipe run may fall under the provisions of the Party Wall Act.
Can I excavate near my neighbour?
Yes you have a right to excavate near your neighbour, but you must inform the adjoining owner by serving a notice, known as a Section 6, if you plan to:
Excavate within 3 metres of a neighbouring owner’s building or structure, where that work will go deeper than the neighbour’s foundations
Excavate within 6 metres of a neighbouring owner’s building or structure where that work will cut a line drawn downwards at 45 degrees from the bottom of the neighbour’s foundations.
You must tell your neighbour on the notice whether you propose to strengthen or safeguard the foundations of their building or structure. This could include underpinning. The notice must be accompanied by plans and sections showing the depth and location of the excavation to be valid. Not sending this information is a common mistake and can cause delays.
The Act sets out the precise information you must tell your neighbour and you must tell your neighbour in writing. It is common to use a standard Party Wall Notice to make sure that this is done.
We’ve uploaded templates to help you. You may feel happier appointing a party wall surveyor to do this for you. Collier Stevens has a competitive fixed fee service which includes serving the correct notices.
When must I serve a notice?
At least one month before the planned starting date for the excavation.
What happens after I serve a notice?
If the adjoining owner gives a notice within 14 days agreeing to the excavation, the work (as agreed) may go ahead. If the adjoining owner does not respond, or objects to the proposed work, a dispute is regarded as having arisen.
The neighbour may then wish to appoint a party wall surveyor and have the issue resolved with a party wall agreement or party wall award. This process can take time especially if the proposals are complicated — for instance if you want to build a basement.
Your neighbour’s surveyor may seek the advice of a structural engineer on complicated schemes to advise him as to the suitability of the structural solutions proposed. They are often referred to as checking engineers.
After the work has been completed, the adjoining owner may request particulars of the work, including plans and sections.