10 Ways to Keep Your Home Cool in a UK Heatwave
UK heatwaves are becoming more frequent and more intense. Here are the most effective strategies for keeping your home bearable — and the honest limit of what works without air conditioning.
The UK reached 40°C for the first time in recorded history in July 2022. Heatwaves are now a regular feature of the British summer, and homes designed for cold retention are poorly equipped for the reverse. Here are the most effective strategies, ranked by effectiveness.
1. Air conditioning (most effective)
Nothing else on this list comes close to the cooling capacity of a properly sized air conditioning system. If you experience multiple heatwaves per year and your home becomes uncomfortably hot, this is the only reliable solution. Every other item on this list is a workaround.
2. Night ventilation strategy
Open all windows and doors wide from sunset until the outside temperature exceeds the indoor temperature (typically early-to-mid morning). Then close everything — windows, curtains, blinds. This flushes the building's thermal mass with cool night air. In a well-insulated brick or stone property, this can keep temperatures comfortable until midday or later.
3. External shading before the heat enters
Closing internal blinds is moderately effective. External shutters, awnings or external blinds are significantly more effective because they prevent solar radiation from reaching and heating the glass itself. If you're considering external shading, south and west-facing windows give the greatest benefit.
4. Eliminate internal heat sources
On hot days, avoid using the oven — cook with a microwave, air fryer or barbecue outside. LED lighting generates much less heat than halogen or incandescent — if you still have older bulbs, consider switching. Switch off computers, televisions and other electronics when not in use.
5. Strategic fan use
Fans work best when the air temperature is below your skin temperature (approximately 35°C). Place fans to create cross-ventilation — drawing air in through a lower, shadier opening and exhausting through a higher, sunnier one. At night, placing a fan in a window facing outward can help exhaust hot accumulated air.
6. Cooling before sleeping
The body needs to lower its core temperature to initiate sleep. A cool shower before bed, cool (not ice cold) water for drinking, and breathable bedding (cotton or linen rather than polyester) all help. Some people find a hot water bottle filled with cold water and placed at the feet effective.
7. Damp cooling
Hanging damp sheets across doorways or windows can provide evaporative cooling in dry heat — but in humid UK summer conditions this is less effective. It also increases indoor humidity, which can make the space feel less comfortable even if the temperature drops slightly.
8. Prioritise bedrooms over living spaces
If you have a single room that's air conditioned, make it the bedroom. Loss of sleep due to heat has measurable health impacts and the effects compound over multiple nights. A comfortable sleep environment is more important than a comfortable daytime living space.
9. Reduce thermal mass in the sun
Objects that absorb and re-radiate heat — dark-coloured surfaces, thick carpets, heavy curtains — delay cooling in the evening. During a heatwave, removing or covering dark surfaces can marginally help your home cool more quickly once temperatures drop.
10. Stay on the ground floor
Heat rises. Ground floor rooms are typically 3–5°C cooler than the upper floors of a house during a heatwave. If you have a loft conversion used as a bedroom, a heatwave will make this obvious — lofts can reach temperatures 10°C higher than the ground floor on hot afternoons.