When warmer weather hits, it can be difficult to know how to cool down in the UK with most households not having the luxury of air conditioning.

While electric fans are a go-to for many, you might also be tempted to open your windows to cool down but how effective is this and should you keep them closed instead?

To settle the debate, John Small, Housebuilder in the UK and owner of Ty Eco, has explained how to keep your house as ‘cool as a cave’ this summer.

Should you open or close your windows during a heatwave?

Ty Eco founder John follows the PassiveHaus UK principles which help new-build and re-fitted homes beat the heat.

How to cope with hot weather

He said: “If it’s cooler inside than outside, you should keep your windows closed.”

John added that while it can be tempting to open your windows during a heatwave, you’re only bringing the warm heat inside, making your home hotter.

He explained the science behind his advice: “Heat enters our house in two ways: solar radiation from the sun, and hot air.

“We want to limit both, by closing the windows and curtains – but, if it reaches a point where the temperature inside the house is equal to that outside, then you should open the windows, keeping the curtains closed.”

If you want to open the windows, there’s a specific time you can try it.

John explains that you can open your windows to keep cool in the late evening through to early in the morning until 9am.

He advises keeping windows closed outside of this period.

John added: “For those really feeling the heat, it may be that your home is actually warmer inside than out, in which case, I would advise you to reverse the advice, but be wary, how it feels, and the actual temperature is deceiving, so always use a cheap temperature probe.”

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If you’re still struggling to keep your house cool, John said you could use privacy film.

This is used in hotter climates around the world and increases your windows’ ability to bounce away heat will low your homes internal temperature.

A reflective film allows to block the radiation heat from the sun and offers extra privacy.

He said the heat film is also designed to allow the same amount of natural summer light into your home.