The Dutch climate continues to become hotter and hotter, raising the question of what to do with the homes that were originally built for a cooler climate and now become dangerously overheated in summer. During the extreme heat this June, for example, more than 3,500 people died in the Netherlands. Furthermore, in every future scenario by the national weather service, KNMI, the Dutch summers will continue getting warmer.

Experts have now spoken to NU.nl about how they think that the new homes that are actively being built to meet construction goals must be better designed to prevent overheating. Experts told the newspaper that design rules for new buildings are not suitable for the rapidly changing climate.

“The homes we design now will still be standing in 2050,” said Jeroen Kluck from the Amsterdam University of Applied Sciences, who specializes in climate-resilient cities. “We should be calculating with the 2050 climate.”

That is not currently happening. The homes that were built starting from 2021 meet the standards calculated based on the cooler climate back in 1996 and 2015. New building standards that use 2033 climate have reportedly been done, but it will take years before they become solidified.

Experts argue that the process is too slow, as the Netherlands plans to build 100,000 homes a year, meaning that many buildings will likely not be built in a way that prevents overheating.

There are no legal overheating standards for existing homes. Earlier Investico research found nearly 10 million people in the Netherlands live in a home that can get too hot, including 2 million aged 65 and older. Even new, well-insulated homes can get too hot during a heatwave.

In cities and larger towns, heat lingers longer at night than in the countryside, said Saskia Hegeman, an adviser at engineering firm Nieman. In the cities, the heat can be up to 8 degrees higher, and nights provide little cooling. When that happens for long periods of time, the heat will start building up inside a home.

“The body cannot shed that heat well, and the heart has to work harder,” Keon van der Sanden, a thermophysiologist at research institute TNO, told NU.nl. That, in turn, can pose a possibly deadly risk to older adults, chronically ill individuals, and pregnant women.

The Ministry of Housing and Spatial Planning said overheating standards for new homes are “no longer current” and are being reviewed.