Subsidence, settlement and heave
What should you ask if the survey names both a tree and a possible drain leak beside the same crack?
Ask which one the surveyor actually saw evidence of, and do not pick a favourite. A tree on clay can dry the soil. A leaking drain can wash soil away. The Association of British Insurers treats ground movement as subsidence when the ground goes down. A home survey does not test the soil and does not camera the drain unless that was agreed.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
The useful next step is often to separate them. A CCTV survey looks at the pipe. An engineer or a soil investigation looks at the ground. Doing both at once may be what the corner needs, or it may be two invoices for one unanswered question. The survey should say what was visible: roots, a wet gulley, a staggered crack, the species if known. It should not pretend to have done the tests.
There is no RICS price for a camera or a trial pit. Ask each firm what they will inspect. Do not fell the tree and dig the drain in the same weekend before anyone has said which is affecting the wall. A home survey is still a visual inspection. It does not become a drain test because a tree is in the garden.
What should you ask your surveyor?
- What did you see of the drain, as against the tree?
- Are you recommending a camera, an engineer, or both?
- Is the soil described, or assumed?
What are the typical next steps?
- Commission the investigation the evidence points to first.
- Do not price underpinning while both causes are still open.
- Give each specialist the survey sentence, so they are not guessing from a photo.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
If the camera is clear, is the tree innocent?
Not automatically. A sound pipe removes one suspect. The tree and the crack remain.
If the tree is small, can you ignore it?
Size and species matter, and the survey may not know the species. Small is not a soil test.