Cracks in walls: what homebuyers should ask about subsidence

Finding a crack during a viewing can be unsettling, but the appearance of a single crack does not establish its cause. The useful next step is to gather history and obtain appropriate professional advice, rather than deciding from a photograph alone.

Cracking and subsidence are not interchangeable

Buildings can show cracks for different reasons. Shrinkage, thermal movement, alterations and other mechanisms may need consideration alongside possible ground movement. RICS describes subsidence as downward movement of foundations caused by changes in the supporting ground; it is distinct from settlement.

The pattern, location and development of a crack matter, as does the wider building. Avoid treating an online width chart or a neighbour’s experience as a diagnosis. A professional may need more information or monitoring before reaching a conclusion.

What information should you ask for?

• When were cracks first noticed, and have they changed?
• Has the property had structural investigations, monitoring or repairs?
• Are engineer’s reports, completion records or guarantees available?
• Have there been relevant insurance claims?
• Have nearby drainage problems or alterations been investigated?

Ask for the actual documents, not just a verbal assurance that a problem was dealt with. Your conveyancer should advise which records and disclosures are needed for the purchase.

What should a surveyor know before the visit?

Share clear photographs if you have permission, the position of the cracking and any seller’s documents. Also mention sticking doors, uneven floors or other observations without assuming they share a cause. Early disclosure helps the provider assess whether the proposed survey is suitable.

A general home survey may recommend a structural engineer, drainage investigation or further monitoring. It cannot always determine whether movement is historic, ongoing or likely to recur from a single visual inspection.

Insurance and repair implications

Investigate whether buildings insurance is available on terms you can accept. Ask your adviser about any existing claim, proposed transfer of arrangements or exclusions. Do not assume that a repaired appearance or an old guarantee automatically answers the insurer’s questions.

Repair quotations should follow the appropriate diagnosis and scope. Cosmetic filling may make a surface look better without addressing the reason for movement. Equally, not every crack justifies major structural work.

Making the purchase decision

Bring the professional findings, insurance position, legal information and your budget together before deciding. Some buyers are comfortable with a well-documented history; others prefer a simpler purchase. This guide cannot assess an individual crack, so act on property-specific advice and investigate unresolved material concerns before committing.

Keep exploring

• Your home survey has arrived. What happens next?
• Can you renegotiate a house price after a survey?

Further information

RICS: subsidence consumer guide

Published 9 November 2026 by HomeSurveyNow. General buyer guidance, not a diagnosis, property valuation or legal advice. The property, agreed service and advice from your own professionals determine the appropriate next steps.