Does keeping the actual windows shut help?

[Crunchymum]

I always keep the blinds / shutters / curtains closed but I've never quite managed to keep the actual windows closed too (I open them early or have them all open a crack or even have them wide open behind the shutters)

If it genuinely works I will do it properly tomorrow 😓

It does. I know it's really hard to get your head around but it's about preventing hot air from flowing in.

This is a totally different thing to preventing the room being heated by the actual UV rays. That's what you're doing when you close curtains/blinds/put tinfoil up on windows etc.

But ideally, do both for best heat prevention.

If the air temperature is hotter outside, keep the windows closed. As soon as it falls lower, feel free to fling all windows open.

It feels totally counterproductive because we don't normally ever get such high air temperatures in the UK, but it definitely works. It will still get hot inside, but not as hot as it would with the windows open. You'll get that lovely effect, if you go out, of it being a cool refuge inside.

Caveat - if it's just a degree or two hotter AND there is a through breeze, then it's worth opening windows. But if there's no breeze it's best to stick religiously to the indoor/outdoor temp rule.

It does sound like a daft idea but it does work

Hot air comes in when the window is open

Have tinfoiled all windows and covered the back of the foil as much as I can on main windows with cardboard to give extra blocking of heat. House is 21 degrees, outside is 28.

It works, you feel the house is cool when you walk in from outside. But you must cover every window including small door windows and then close blinds and curtains over it.

I think it depends on how the windows are located. My house is semi, so we have no windows on north side. So I keep the window on south shut. But I keep the windows on west and east open. The air goes through the house, and feels cooler.

All blinds, doors and windows shut in my house today. I have fans on and it's ice and cool.

Doesn't that make the house dark? I couldn't sit in a dark house all day.

I'm (for some reason) slightly embarrassed to admit I have tinfoiled my kitchen and dining room windows as they get the sun from 12pm til sundown and our house is usually unbearable on hot days. For the first time ever it is cooler indoors than out, I'm ecstatic! Some windows are on night lock so just open a crack but the majority are closed, I wish I'd closed them all before I did the tin foil as the rustling noise is annoying

Double glazing stops the transfer of heat. Heat moves from hot area to cold area. So right now the glazing is keeping the heat outside!
I keep windows and curtains closed on the sunny side of my house and open them when they're in the shade.
It's the same as a flask keeping it's contents hot or cold.

We've had windows open from 6:30am until 8, they let a lot of cool air in, closed the windows nearer the temperatures equalising, also closed all curtains. Been out today and come home to the house being 22 degrees, it's 30 outside so it has helped

So the rules are

• open the windows as wide as possible, as many of them as possible, EARLY in the morning and late at night. This is to increase the amount of cold air coming into the house.
• have curtains closed as soon as the sun starts shining on them.
• close the windows that are in the sun. But if possible keep the ones who are not in the sun slightly open. This works even better if you can do that with a few of them so there is some air circulation.
• you can also leave the windows opened (when not in the sun) and leave a frozen bottle of water in front of the gap. The difference of temperature will help the air moving and will introduce cooler air.
• you can also put the frozen bottle of water in front of a fan.

Fwiw there is a reason why people have shutters in warm countries rather than curtains. It’s much easier to regulate the temperature that way.

Preferable to sitting in a 38-degree house all day like tomorrow, surely?

Yep I agree with everyone else! It does sound odd to shut everything when it starts hotting up but it’s worked a treat here today. Our garden is south facing and our patio has been like a furnace today. Can’t stand on it barefoot and had to carry the dog out to the lawn for a wee bless her. But indoors it’s been lovely and much cooler. Not dreading tomorrow quite as much now!

Our house is south facing so always bakes in even a little bit of sun. The air gets so stale and stuffy.

We always open windows but we have the advantage of living somewhere really windy - so there's always a through draught. (Knocks pictures off walls!)

Amber warning here (Scotland, just extended to cover where I live)

So we'll have the windows open.

It's really grey here atm. Warm but grey. Even the wind is warm. Which is truly unusual. I've been able to sit in the garden this afternoon, even with the wind. Normally the wind would make our garden freezing and we'd head inside.

Well I'm at work all day tomorrow in a factory, so sitting at home in 38 -degree (although it's forecast 30 where I am), will feel lovely compared to that.

Definitely closed for me. Been closed since 5am, opened them at midnight to let some cooler night air in and it’s been a nice 22.5 for most of the day.
Just opened the patio door to put some washing on the line - felt like I’d stepped onto the balcony on holiday 🥵 and came back in and it’s now 23.7.

I have a temperature reading on my alarm clock and I look at the weather to see when outside is cooler than in. Tonight it's about 10pm

We open them in the morning and close them as the temperature rises. Yes it works. Keep curtains and clinds shut too. We also stay downstairs - it is cooler to sleep downstairs in this weather.

We open all of our windows first thing in the morning to help cool the house down. We close and draw the blinds when it starts to warm up. Now the sun is off my daughters room I’ve opened all the windows again and her room thermometer has dropped from 27 to 25 in about half an hour!

I leave blinds down (external blinds/shutters so the sun doesn’t hit the glass) and will only open a window if there’s a breeze. If just hot air I leave it shut, until the sun moves from that side of the building.

you need something on the outside of your window to stop the sun hitting the glass and avoid the greenhouse effect. If you don’t have shutters like in the med you can buy external curtains in awning type material, or just put up some awning or an external screen. Not sure how feasible this is with Victorian bow windows though. My aunt had a bamboo screen she’d move in front of her front windows on hot days.

It’s really not rocket salad.

My flat only faces one way so no through draught. I need to rig up something for the bathroom and small bedroom behind the curtains.

I left all the windows open overnight and shut them at 6 this morning. Currently we are at 28 in the living room which is the hottest room. It is much hotter without keeping windows shut. I am opening windows in about an hour and will leave them open all night.

My aunt had a bamboo screen she’d move in front of her front windows on hot days.

That's a good idea. Might sort that out for next year if we're going to get heat like this again.

Unfortunately doesn't work for me. Also a new build. Tested it today in the hottest room of the house. Temp was 29 this afternoon after leaving windows closed all day. Opened them and still 29 so I'm sticking with my open windows/closed curtains/plenty fans routine.

Of course.

Does keeping them closed in winter keep the house warmer indoors?

24 in our ground floor.

Won't open anything until I know it's cooler outside than I.