Using just an Allen key, you are able to keep your home feeling warmer for longer by putting your windows into winter mode. Many people may not realise that their UPVC windows have summer, neutral and winter options.

In a revealing YouTube video, A Man About The House demonstrated how to put UPVC windows into winter mode. By opening your window, you should see stick-out bits either on the inside of where you close the window, or on the window side itself.

These circular stick-out notches will have an indent to demonstrate which setting the window is in. The lined indent facing north means it's in neutral mode, but it can easily be turned the right way with an Allen key.

"All you want to do is turn this so it pulls the window into the frame a little bit tighter," said the YouTube hero. 

If you turn it anticlockwise, "it will slacken and make it more draughty", whereas turning it clockwise, "it will tighten the window sash and put it into winter mode".

This minor adjustment will make the window tighter, and forcibly more stiff to close, but this means less warm air can escape and less cold air can enter the home.

A simple draught-excluding adjustment such as this will simply help to lower your energy bills as you won't need the heating on for as long.

"You don't want to over-tighten it," he cautioned. "Because you're at risk of basically squashing or damaging the seal."

He added: "Under adjustment will mean that you're allowing drafts and the actual window sash isn't closed into the frame correctly."

This is why "it's worth having a little bit of a play about" to find the right adjustment for your home.

Once he made the best adjustment for his window, the YouTube star said he "can't really feel any draughts".

"It's just a matter of going around all the windows checking and adjusting where you need to," he said.

And there you have it – a simple and cost-effective way to reduce your energy bills and make your house feel warmer.