Subsidence, settlement and heave
What is stepped cracking, and what does it not prove on its own?
Stepped cracking follows the mortar joints in a staircase pattern, usually in brick or stone. It means the wall has moved enough to open the joints. It does not, by itself, tell you whether the ground has dropped, a drain has washed out, a lintel has failed, or the movement stopped years ago.
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?
Surveyors record direction, width, and whether the crack is tapered, and they look at the ground, the drains, the trees and the openings nearby. The Association of British Insurers describes subsidence as downward foundation movement. A stepped crack is a symptom that can fit that description and can also fit other causes. A single visit does not date the crack.
Do not fill the joint and call it monitored. If the report recommends investigation, that means someone must test the cause, often a drain survey or an engineer, not a bag of mortar. There is no ABI price for a stepped crack, and no RICS price either. Get the investigation the sentence actually asks for before you name a reduction.
What should you ask your surveyor?
- Does the step taper, and does it run through openings or stay in blank wall?
- Is there a tree, a drain, or a downpipe at that corner?
- Are you saying the movement is historic or that you cannot tell?
What are the typical next steps?
- Photograph the crack with a ruler. Do not rake it out before anyone else has seen it.
- Ask the seller whether it was repaired before and when.
- If the rating says investigate, book that investigation. Pointing is not the investigation.
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
Is a hairline step harmless?
Hairline does not mean historic. It means narrow. Ask whether the surveyor saw repair, displacement, or only the line.
Should you tell an insurer before you own the house?
You cannot claim on a policy you do not hold. You can ask your proposed insurer what they need declared. The survey does not make the claim.