As summer arrives, everyone loves the warmer weather, but the challenge of keeping cool indoors without driving up energy bills is significant. Homes in Britain are built to keep us cosy during our chilly winters, resulting in indoor spaces that can often feel like ovens as temperatures rise.

But fear not, one expert has shared the "caveman method" - a cheap and easy way to keep your home as cool as possible during the heatwave. You may feel it makes sense to try and keep a breeze going through the house by keeping the windows open, but this is the wrong thing to do.

When it is super hot, this will only blow more hot air into your house. The best way to keep your house cool is to try and get it to mimic the conditions of a cave.

Joseph Holman, CEO of Green Doors, says to keep your home cool, you should "think of it like a cave". He told Tom's Guide: "A cave is cool in heatwaves because it is dark and doesn't have direct sunlight or a direct entrance for the heat. You want to probably mimic that."

Holman recommends keeping everything closed when it's hot. Joseph says you want to "reduce sunlight and stop the movement of the outside air inside; even switching off the lights will help you with that".

If you've got air conditioning, Joseph adds that you wouldn't be opening doors or windows through fear of letting the cool air out and wasting it. In reverse, if you're not running AC, but you open the doors or windows, you're letting hot air in.

But there's long-term methods you also want to consider. For this, Joseph says: "If you want to protect your home from the heat longer term, I would recommend investing in tinted film for windows to reflect the heat, as well as installing integral blinds as a smart way to control the temperature in your home.

"You can install integral blinds without changing the doors and windows themselves, simply by changing the glazing units." He adds: "They are a great space-saver and will last longer than external blinds, which can be damaged much more easily."

He also recommends modern glass for its superior reflective qualities, as well as roller blind canopies rather than traditional curtains as these shut out light better.