Overview
- Spencer advises using a 10p coin at viewings as a quick gauge, noting cracks narrower than roughly 3mm may be superficial and urging buyers not to jump to conclusions.
- Insurer AXA defines subsidence as ground sinking that can unbalance foundations, leading to moving walls and floors that may render a home unsafe if left unchecked.
- AXA says warning signs include cracks wider than a 10p, diagonal cracks that are wider at the top, cracks visible inside and out, fissures starting at ground level or under the damp‑proof course, and sticking doors or windows.
- Routine crack repairs can cost about £1,400–£1,700, while subsidence remediation averages around £12,500 and can, in some cases, cut a property's value by about 20%.
- The Association of British Insurers reports a record £4.6bn in property claims paid in the first nine months of 2025, using the figure to press for climate‑resilient housing design.