Subsidence, settlement and heave
The report mentions clay and a willow, and it does not record a borehole. What soil test has not been done?
No borehole was recorded, so the soil test that would describe this clay has not been done. The report mentions clay and a willow. That is a comment linking a high-demand tree with a soil that can shrink and swell. It is not a laboratory result and not a hole in the ground. Plasticity, moisture profile and desiccation were not measured. The survey can flag the combination it was told about or could see. It has not tested the soil under the house.
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?
A willow near a building on clay is a known reason to ask about foundations and about how the tree is managed. The comment does that asking. A borehole would recover soil from known depths so someone can see what the ground actually is. None is in the report. The inspection did not auger the garden, did not send a sample away, and did not measure how dry the clay is beside the willow. Mentioning the tree is not a substitute for that test.
Ask the solicitor whether any soil report or tree survey already exists, and if the willow is close enough to matter, instruct a ground investigation rather than rereading the sentence. An arboricultural note on the tree is a different instruction again. Do not tell a lender the foundations have been checked against shrinkable clay. The survey named clay and a willow. It did not bore the soil.
What should you ask your surveyor?
- Did the report record a borehole, or only a comment on clay and a willow?
- How was the clay identified, if it was identified at all?
- What of the willow’s distance and the foundations was left unmeasured?
What are the typical next steps?
- Treat clay and willow as a comment, not as a soil test.
- Ask the solicitor for any existing ground or tree report.
- Instruct a borehole investigation if the foundations must be understood.
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 willow is pollarded, has the soil risk gone?
Pollarding is tree management, not a soil test. The survey mentioned clay and a willow and did not record a borehole. It did not measure whether the clay is shrinkable or dry. Cutting the crown does not, by itself, become the missing test, and the report has not said the ground is safe.
Can last summer’s dry lawn stand in for the borehole?
No. A dry lawn is the surface in one season. A borehole is a sample from depth, and none was recorded. The comment on clay and willow is not that sample. The inspection did not test the soil, so the lawn cannot be rewritten as a ground investigation.