Saturday 28 November 2020

That sinking feeling: houses rated on state of foundations, but status unclear

Buildings in Groningen province have been damaged by sinking ground levels caused by gas extraction. Photo: Graham Dockery

A private foundation has published plans to grade every home in the Netherlands based on the state of its foundations to alert owners to potential subsidence.

The expertise centre on foundations KCAF says it is introducing the labelling system in response to a growing number of incidents where buildings have sunk or collapsed as a result of long-term drought and low groundwater levels.

KCAF chairman Dick de Jong said around one million of the 7.7 million houses in the Netherlands were vulnerable to subsidence. The problem is particularly acute for houses built before 1970, which mostly have wooden foundations. In around 250,000 cases the situation is urgent.

‘We come across serious situations,’ De Jong told NOS. ‘A label should prevent the problem getting worse without anybody knowing.’

The foundation’s label is based on a model to highlight which areas are most prone to ground subsidence, based on satellite images, the ground water level and the type of soil and ‘gives and indication of the risk of foundation problems,’ the website states.

However, the label is an indication and has no formal status, the website states. Nor does it take into account if home owners have actually had their foundations checked or improved.

For sale

A spokesman for the Dutch real estate agents association NVM said a new approach to valuing houses will be introduced from next July and that will include more focus on the state of a building’s foundations.

However, he said he was not aware of any requirement to include the foundation label in valuation reports, or if it had any legal standing.

A bad foundation label could have a serious impact on a the price of property, because the bill for upgrades can run into hundreds of thousands of euros.

In September a 20-metre stretch of canal wall in Amsterdam sank in less than a minute, prompting the city council’s infrastructure chief Sharon Dijksma to commission a report into the state of 100km of canals. Some experts say the repair bill could total €2bn.

Thank you for donating to

The team would like to thank all the generous readers who have made a donation in recent weeks. Your financial support has helped us to expand our coverage of the coronavirus crisis into the evenings and weekends and make sure you are kept up to date with the latest developments. has been free for 14 years, but without the financial backing of our readers, we would not be able to provide you with fair and accurate news and features about all things Dutch. Your contributions make this possible.

If you have not yet made a donation, but would like to, you can do so via Ideal, credit card or Paypal.