Subsidence, settlement and heave
The house sits in an area associated with brine extraction, and the floors were level on the day. Has the survey cleared that ground instability?
A level floor on the day of the survey has not cleared ground instability in an area associated with brine extraction. Level boards, or a level screed, say what the surfaces did during the visit. They do not speak for the ground over time, and they do not cancel the association the location carries. The survey has not investigated brine workings, and it should not invent a depth or a history for them.
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?
Brine extraction is a ground question. A floor that reads level with a spirit level is a building question, limited to the spots that were checked. Both can be true together: an area with that association, and floors that were level when seen. Writing 'cleared' would pretend the visit was a ground investigation. It was not that kind of investigation.
Tell the solicitor about the area and tell them the floors were level, as two sentences. If a specialist mining or ground report is needed, instruct it separately. Do not borrow a Coal Authority style of comfort from a level floor, and do not alarm the structure with a depth nobody measured. The survey's limit should stay visible.
What should you ask your surveyor?
- Which floors did you check, and were they level only in the rooms you entered?
- Are you refusing to clear brine-related ground risk because of that level?
- Did the visit include any ground investigation, or only the building?
What are the typical next steps?
- Do not treat level floors as a clearance of ground instability.
- Keep the brine-extraction area and the floor comment as separate findings.
- If the ground needs a specialist view, instruct that separately.
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 every floor is level, is the ground stable?
Not proved. Level floors on one day do not clear an area associated with brine extraction. The survey did not investigate that ground.
Can you state how deep any brine workings are?
No. No depth was established on this visit, and none should be invented to make the location sound either safe or unsafe.