# London subsidence risk from extreme heat

> Live situation record from CLSTR: https://clstr.news/situations/london-subsidence-risk-from-extreme-heat
> Updated: 2026-09-11T08:00:29.000Z. Sources: 8. Developments: 2.

London and southeast England are facing significant subsidence risks driven by extreme heat and dry weather. The intense heat dries out the clay-based soil, causing a ‘shrink-swell’ process where the ground contracts and shifts, leading to structural damage such as wall cracks, warped windows, and shifting foundations.

Insurance data from the Association of British Insurers (ABI) indicates that subsidence-related claims reached a record high in the last quarter, with average household claims rising 15 per cent compared to 2025. High-risk areas include boroughs such as Westminster, Kensington, and Chelsea.

Older properties are especially vulnerable due to shallower foundations, and experts note that tree roots can exacerbate the drying of the soil. Projections suggest that by 2030, some parts of the city could see 100% of properties facing possible or probable subsidence risk.

## Timeline

### 2026-09-11: London buildings face subsidence risk from extreme heat

Extreme heat and dry weather are causing clay soil in London to shrink, leading to widespread building subsidence and structural damage across the city.

2 sources. https://clstr.news/cluster/london-buildings-face-subsidence-risk-from-extreme-heat

### 2026-08-23: London homes face record subsidence risk following heatwaves

Successive heatwaves in London have dried out clay soil, causing record subsidence insurance claims and significant structural damage to homes in boroughs like Westminster.

6 sources. https://clstr.news/cluster/london-homes-face-record-subsidence-risk-following-heatwaves

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Cite as: London subsidence risk from extreme heat. CLSTR, https://clstr.news/situations/london-subsidence-risk-from-extreme-heat