Does opening a loft hatch cool house in hot weather? Should you leave attic open to let hot air up in heatwave

The UK is currently in the grips of another hot spell, with temperatures expected to soar to 32C over the coming days.

The UK Health and Safety Agency has issued an amber heat alert due to the unusual September weather which is in force until Sunday night (10 September).

The heat is impacting large parts of England and Wales and is expected to stick around for some until the weekend according to the Met Office. People are trying lots of ways to stay cool from tin foiling their windows to even drinking hot drinks.

But what about your attic? Could you cool your house down if you opened your loft hatch? Here’s everything you need to know.

Does opening my loft hatch help with hot weather?

Yes, opening the loft hatch in your attic will help your house cool down during hot weather. Often, the warmest area of your home is your second floor. As heat rises, if the warm air has nowhere further to go, it will stick around, leaving you with a hot and stuffy bedroom.

However, if you open your loft hatch, as hot air rises, the warm air will go up into your loft. If you have a loft conversion, opening your loft windows is an even more effective way to ensure that the hot air trapped in your home will have somewhere to escape when it rises.

Why does hot air rise?

Hot air rises because when air is heated up it expands. When the air expands this causes more space between the air molecules. It becomes less dense and floats upwards, this is the same method that helps hot air balloons float.

This means that when there is hot air in your home it will rise, if it has nowhere else to go it will stay in the top level of your house, leaving it to be warm and stuffy. As this is often the area where you sleep, it can leave you with an unpleasant night ahead.

If you give the hot air somewhere to go, by opening your loft hatch, it will rise further and go up into your attic, leaving your bedrooms a lot cooler.

What other tips can help keep my house cool?

This is just one helpful tip to keep your house cool during warm weather. Whilst you may think that opening your windows will help cool your house, if it’s warmer outside than inside, this could end up doing the opposite.

The NHS advise you to :”Shut windows and pull down the shades when it is hotter outside. You can open the windows for ventilation when it is cooler.

“Keep rooms cool by using shades or reflective material outside the windows. If this isn’t possible, use light-coloured curtains and keep them closed (metallic blinds and dark curtains can make the room hotter).”

There has been a recent trend to use tinfoil to help cover up windows to help reflect the sun.

Another study from 2012 suggests that drinking a hot drink can help you cool down.

And a top tip to help cool air circulate throughout your home if you don’t have a fan is to hang up wet, cold towels around doors and windows.