A closer look at subsidence

11 October 2017

Subsidence – it’s one of every property owner's worst nightmares, but relatively little is known about it. Justin Clarke, Director of Underwriting and Pricing at NIG, takes a closer look at the implications it can have for landlords, both residential and commercial.

As many as one in five homes in England and Wales may be at risk of subsidence damage, which affects as many properties as flooding on an annual basis.

Subsidence occurs when the ground under a property sinks lower, causing a downward movement of the foundations. This puts a strain on the building’s structure, and cracks start to appear. The very thought of it strikes fear into the hearts of property owners everywhere…

What causes subsidence

There are numerous causes of subsidence, however, soil shrinkage is the main culprit and is responsible for around 75% of all subsidence claims. Other common causes include tree roots absorbing water and causing soil shrinkage and leaking drains and pipes, which can soften the ground around a property and reduce its load-bearing capacity, resulting in foundation movement.

Weather can also play a role in increasing the risk of subsidence with long periods of dry, mild weather putting the UK at risk of a subsidence ‘event’ – a period when there is a significantly higher than average number of subsidence claims.

However, these are not all that common. Despite a few near misses, the last time the UK experienced a subsidence event was 2006, when we experienced a particularly dry winter.