Keeping rental homes cool during heatwaves is a major headache for tenants in the Netherlands, according to new research by national statistics agency CBS.

Last year, 34% of households said they could not keep their homes cool on hot days, and the problem was particularly acute for tenants and people living in older buildings.

In total, some 55% of people living in a home rented from a private landlord had trouble with the heat, as did 46% of those living in rent-controlled properties.

Opening windows in the evening and at night was the most common solution, while 60% kept windows and curtains closed during the day.

The research also showed that less than 5% of rental homes in the Netherlands have permanent air conditioning, compared with 18% of owner-occupied properties. But in Limburg, the most southerly part of the Netherlands, almost one in three households had air conditioning, the CBS said.

The temperature in the south is due to hit 30° on Friday and could top that on Saturday, according to the KNMI weather bureau.