Buildings are sinking and cracking in one of Europe’s largest cities

As blistering temperatures baked London this summer, people started to notice strange things happening to their houses: zig-zagging cracks suddenly appeared across walls, doors got stuck, windows warped.

Extreme heat brings many problems for a country not built for it: Schools close, train tracks buckle and — it turns out — houses sink.

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London, along with other parts of southeast England, is at the epicenter of a subsidence problem, which is being fueled by unusually hot and dry weather. As heat waves dry out the city’s soil, the ground is shifting and shrinking, pulling buildings down with it.

“Subsidence is one of the most damaging geohazards in the UK today,” said a spokesperson for the British Geological Survey, or BGS. And experts warn the problem is only going to worsen as humans continue to burn fossil fuels and heat the planet.

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London, like many parts of the UK, is built on clay. When wet, it acts like a sponge, sucking up moisture and expanding; in hot and dry conditions, it loses water and contracts. It’s a process called “shrink-swell,” and when the shrink occurs unevenly under the foundations of a building, it can lead to subsidence.

The city is particularly at risk because the specific kinds of clay soils on which it sits contain expansive minerals that are highly susceptible to changes in moisture. It’s also typically exposed to some of the country’s hottest temperatures.

An important factor is trees and plants. When it gets hot, their roots drive deeper and further in search of moisture to suck from the soil, often seeking out the damper ground beneath nearby homes — drying it out and causing it to shrink.

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Older properties tend to be more vulnerable to subsidence, often due to shallower foundations — and more than half of London’s homes were built before 1945.

Across many parts of the city, 100% of properties are projected to face possible or probable subsidence risk in 2030, according to data from the British insurance company Aviva. This includes central areas such as Kensington, the City of London and Westminster.

But it’s a problem that goes much wider than the capital. When subsidence expert Bob Gibson started in the business 40 years ago, the issue was mostly in London and the south-east of England. “But with climate change it is now affecting many other parts of the UK as well,” said Gibson, who is the director of Building & Structural Consultants.

Whenever there is a hot dry summer, there is a “surge” of subsidence claims, Gibson said. In 2025, when the UK endured an extraordinarily hot summer, the insurance industry paid out a record $415 million in subsidence-related claims, up 10% compared to 2024, according to data from the Association of British Insurers, or ABI.

The record may soon be broken. “This year is shaping up to be the biggest ever, as it is the second of two consecutive drought summers with multiple heatwaves,” Gibson said.

Insurers paid out more than $97 million for UK subsidence-related claims in the second quarter of 2026, and the average claim reached a record $27,000 , more than $2,700 higher than the same period last year, according to the ABI.

“Following the extremely hot and dry weather we saw over July and August this year, it’s likely we’ll see more subsidence claims over the coming months,” said Louise Clark, general insurance policy manager at the ABI.

An Aviva spokesperson said the company had already seen an increase in claims this year and it will likely continue “unless there is significant rainfall.”

Aurelien Morissard/AP

Western Europe breaks temperature record in summer plagued by heatwaves and wildfires

Subsidence is sometimes subtle and slow moving, but it can be hugely damaging and challenging to address.

There are two ingredients to consider in subsidence risk, said Brunella Balzano, senior lecturer in structural design at Cardiff University in Wales. The vulnerability of the building and the hazard itself. In the case of heat-driven subsidence, there’s nothing engineers alone can do to address the hazard. “We cannot remove climate change,” Balzano said.

So, they focus on the building. Interventions can include removing trees and vegetation or constructing barriers to isolate their roots from the house’s foundations and, at the more extreme and expensive end, underpinning the house by pumping concrete beneath the foundations.

As temperatures continue to rise, and subsidence claims spike, some experts fear insurers may no longer wish to take on the risk. “I think it’s possible … that in the near future, subsidence might not be insured anymore,” Balzano said.

In London alone, more than 26% of properties could be affected by 2070 if global warming continues at roughly the current pace, according to BGS data.

People are already struggling to secure insurance in high risk areas, Gibson said. “Insurers are jacking-up premiums hugely, or not inviting renewal of subsidence cover,” he said. This can make people fearful of reporting cracks to their insurers, which could lead to them invalidating their insurance, he added.

Subsidence is rarely a life or death issue. “It sits on the borderline, in between what’s really dangerous and what can be neglected for a while,” Balzano said. It’s nowhere near as dramatic as homes falling into the ocean, being ripped off their foundations by floods, or burned to the ground in a wildfire.

But it’s also not just an irritant. Subsidence can cause major damage, devalue homes, make them hard to sell and cost eye-watering amounts to fix. It’s one more part of the general underlying hum of anxiety-fueling challenges climate change is bringing to people’s lives.

今年夏天，伦敦酷热难耐，人们开始注意到自己的房子发生了一些奇怪的事情：墙壁上突然出现了锯齿状的裂缝，门卡住了，窗户变形了。

极端高温给一个不适应这种气候的国家带来了许多问题：学校关闭，铁轨变形，而且——事实证明——房屋还会下沉。

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伦敦以及英格兰东南部其他地区正处于地面沉降问题的中心地带，而异常炎热干燥的天气加剧了这一问题。随着热浪使城市土壤干燥，地基发生移动和收缩，导致建筑物下沉。

英国地质调查局（BGS）发言人表示：“地面沉降是目前英国最具破坏性的地质灾害之一。”专家警告说，随着人类继续燃烧化石燃料并导致全球变暖，这个问题只会愈演愈烈。

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伦敦和英国许多地区一样，都是建在黏土上的。黏土遇水后就像海绵一样，吸收水分膨胀；在炎热干燥的环境下，它会失去水分收缩。这个过程被称为“收缩-膨胀”，当建筑物地基下方的黏土收缩不均匀时，就会导致地基下沉。

这座城市尤其容易受到侵蚀，因为它所处的特殊黏土土壤含有膨胀性矿物质，极易受水分变化的影响。此外，它通常也处于全国最炎热的地区之一。

树木和植物是造成高温的重要因素。天气炎热时，它们的根系会不断向下延伸，寻找土壤中的水分，常常会扎根于附近房屋下方较为潮湿的土壤中——这会导致房屋下方土壤干燥萎缩。

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老房子更容易发生地基下沉，这通常是由于地基较浅造成的——伦敦一半以上的房屋建于 1945 年之前。

根据英国保险公司Aviva的数据，到2030年，伦敦许多地区的房产预计将100%面临可能或很可能发生的地面沉降风险。这其中包括肯辛顿、伦敦金融城和威斯敏斯特等中心区域。

但这个问题远不止伦敦一地。40年前，当地面沉降专家鲍勃·吉布森刚入行时，这个问题主要集中在伦敦和英格兰东南部。“但随着气候变化，现在英国许多其他地区也受到了影响，”吉布森说道，他是建筑与结构顾问公司的负责人。

吉布森表示，每逢夏季炎热干燥，地陷索赔案件就会激增。英国保险协会（ABI）的数据显示，2025年英国经历了异常炎热的夏季，保险业支付了创纪录的4.15亿美元地陷相关索赔，比2024年增长了10%。

这项纪录可能很快就会被打破。“今年很可能成为有史以来最严重的一年，因为这是连续第二个夏季干旱，而且还伴有多波热浪，”吉布森说。

据英国保险协会 (ABI) 称，2026 年第二季度，保险公司为英国地面沉降相关的索赔支付了超过 9700 万美元，平均索赔金额达到创纪录的 27000 美元，比去年同期高出 2700 多美元。

“鉴于今年 7 月和 8 月的极端高温干燥天气，未来几个月我们可能会看到更多地面沉降索赔，”美国保险协会 (ABI) 一般保险政策经理 Louise Clark 表示。

Aviva 的一位发言人表示，该公司今年的索赔数量已经增加，而且这种情况可能会持续下去，“除非出现大量降雨”。

奥雷利安·莫里萨尔/美联社

西欧夏季高温破纪录，热浪和野火肆虐

地面沉降有时是悄无声息且缓慢发生的，但它可能造成巨大的破坏，而且难以应对。

威尔士卡迪夫大学结构设计高级讲师布鲁内拉·巴尔扎诺表示，地面沉降风险需要考虑两个因素：建筑物的脆弱性和沉降灾害本身。就热力引起的地面沉降而言，仅靠工程师自身无法解决这一问题。“我们无法消除气候变化，”巴尔扎诺说道。

因此，他们将重点放在房屋建筑上。干预措施可能包括移除树木和植被，或建造屏障将它们的根系与房屋地基隔离开来，而更极端、更昂贵的措施则是通过在房屋地基下灌注混凝土来加固房屋。

随着气温持续升高，地面沉降索赔激增，一些专家担心保险公司可能不再愿意承担这种风险。“我认为有可能……在不久的将来，地面沉降可能不再属于保险范围，”巴尔扎诺说。

根据英国地质调查局 (BGS) 的数据，如果全球变暖继续以目前的速度发展，到 2070 年，仅在伦敦就有超过 26% 的房产可能会受到影响。

吉布森表示，在风险较高的地区，人们已经很难获得保险。“保险公司大幅提高保费，或者干脆不续保地陷险，”他说。他补充道，这可能会让人们害怕向保险公司报告裂缝，因为这可能会导致他们的保险失效。

地面沉降很少会危及生命。“它介于真正危险和可以暂时忽视的危险之间，”巴尔扎诺说。它远没有房屋坠入大海、被洪水冲毁或被野火夷为平地那么严重。

但这不仅仅是令人烦恼的小事。地面沉降会造成重大损失，降低房屋价值，使房屋难以出售，而且修复费用高得惊人。这只是气候变化给人们生活带来的诸多焦虑挑战中的一部分。