PWS West Midlands knowledge guide
Excavation Near Neighbouring Buildings
Section 6 deals with certain excavations within 3 metres or 6 metres of neighbouring structures. The tests concern both distance and depth.
The 3-metre rule
Measure from the proposed excavation to the neighbouring building. If it is within 3 metres and will go below the bottom of the neighbour’s foundations, notice is generally required.
The 6-metre rule
For deeper excavation, the Act uses a 45-degree plane projected from the bottom of the neighbouring foundations. This often matters for basements, piling and unusually deep foundations.
Information surveyors need
Foundation sections, levels and distances are essential. Trial pits may be required where the depth of existing foundations is uncertain.
Frequently Asked Questions
Is 3 metres an automatic rule?
No. The depth comparison must also be satisfied.
Do drains count as excavation?
Some drainage excavation can be relevant, depending on depth and proximity.
Why record condition first?
It establishes existing cracks and finishes before excavation starts.
Related guidance
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