Dr Ben Roberts, a specialist in building performance and indoor environments, says the way we manage our homes during hot weather is often counterproductive, leading to dangerously warm indoor temperatures that can affect sleep, health and even lead to death among vulnerable groups.
“With overheating, it’s a simple heat balance problem,” Dr Roberts explains. “We have too much heat going in – and not enough heat going out.
“The sun’s heat comes through windows, hot air infiltrates from outside, and even everyday activities like cooking, watching TV or running appliances all generate heat inside the home.”
According to Dr Roberts, the key to keeping homes cooler is using ventilation smartly – particularly at night, when outdoor temperatures drop.
“Many people open their windows during the heat of the day, thinking it helps – but it actually does the opposite.
“During the day, your home can be a cool battery. The last thing you want to do is bring in hot air.
“Instead, windows should stay closed during the day, with reflective blinds or light-coloured curtains drawn on the sunny side of the house.
“Then, when it cools down in the evening, that’s the time to open your windows and let the cooler air in.”
Dr Roberts also highlights a major challenge in the UK: night ventilation is often limited by concerns over security, noise, and air pollution.
“Leaving a ground floor window open at night can feel unsafe. But it’s exactly what we need to do – ideally paired with an open upstairs window to create a ‘stack effect’ where cool air flows in and warm air rises out.
“In future, we might need to consider secure systems for night ventilation, like barred or filtered windows.”
While high temperatures in the UK may not damage buildings, they do pose a serious risk to people, particularly older adults, young children, babies, and pregnant women.
“Heat can cause short-term issues like dehydration or heatstroke, but also long-term health problems,” warns Dr Roberts.
“One of the biggest impacts is on sleep. On hot nights, people struggle to fall asleep, and that sleep deprivation adds up – reducing productivity, increasing illness risk, and potentially even contributing to long-term conditions like dementia.”
As temperatures are forecast to rise above 30°C in parts of the UK over the coming days, Dr Roberts offers these key tips:
- Keep windows shut during the day to prevent hot air from entering.
- Open windows at night when it starts to cool to increase air flow.
- Use reflective or light-coloured blinds/curtains on sunny sides of the house.
- Avoid dark curtains, which absorb and re-radiate heat indoors.
- Consider safe methods for night ventilation, especially for ground floor windows.
“Ultimately,” says Dr Roberts, “we need to rethink how we design and operate our homes to stay cool – not just for comfort, but for our health.”
To arrange an interview with Dr Ben Roberts, please contact the Public Relations Team via email or telephone 01509 222224.
EXPERT COMMENT VIDEO: Below Expert Comment (raw clips) can be downloaded here
- Dr Ben Roberts - Heatwaves and your home (Playlist): https://www.youtube.com/watch?v=WY0YiSbfW0A&list=PL1V7ef1J9COZnAbi7LeI71UpKF3yebCN6
- Why are our homes getting so hot? — and what’s the secret to keeping them cool?: https://www.youtube.com/watch?v=WY0YiSbfW0A
- How to keep your house cool during a heatwave?: https://www.youtube.com/watch?v=oYFaK8s8PEk
Struggling to stay cool? Here’s exactly when to air out your home!: https://www.youtube.com/watch?v=utXEby2-jac - The worst thing you can do to your home on a hot day (are you guilty of this?): https://www.youtube.com/watch?v=ia3UkyCZ4Go
- How do heatwaves affect our health?: https://www.youtube.com/watch?v=B-IOPJFs_dI
Please credit 'Loughborough University', where possible.
For further video/audio support, please contact h.evans@lboro.ac.uk
ENDS