Hot steamy nights

I recently uprated my double glazing and it is even more efficient. A well insulated loft leaves my house requiring less gas to heat during the colder months but it is now prone to warming up inside, particularly when I work in the office and I have 2 computers on the go, along with myself warming up the area. There is also the increase in the humidity. Opening a window will help up to a point but if there is no breeze, as you say, it will unlikely make a difference and the room will probably get hotter from the outside air.

I have reflective film on the inside of the windows, it reduces light in the house (which I prefer) and the rate of heat absorption so helps keep temperatures lower.

Quite a few people rubbish portable air conditioners but I bought one earlier this year for the hot spells, but I had a plan. I designed and had made up a sheet of Perspex made to spec to fit over the inside of half of the office window, allowing the air-con duct to attach with little or no leak of the hot air from outside making its way in. Today is the first real test. The outside air temp reached 30C, the office was 25C with a stuffy 65% RH. Within an hour of running the air-con the temp in the office is now 23C and the humidity down to 59%. Yes, the air-con unit is quite noisy but I have active noise cancelling headphones and can happily listen to the First Night of the Proms with no distraction.

That’s a great way to do it, the only down side is the noise of the all in one portable units
 
Air con feels like a last resort.

I already have a few different fans.

What I am trying to discuss are solutions which actually reduce the temperature, rather than just blow hot air.
Evaporating water will do this. I’ve seen people use a 12v pc fan and sponge radiator to evaporate a tank of water in a sailing boat. It can get the temp down 5 or 6 degrees.
 
Evaporating water will do this. I’ve seen people use a 12v pc fan and sponge radiator to evaporate a tank of water in a sailing boat. It can get the temp down 5 or 6 degrees.

Isn't that really only useful in very dry climates? Because it greatly increases humidity. That's what I've read anyway!

I'm thinking heat reflecting window film is the best solution so far. I reckon that will keep a house at least three degrees cooler than curtains with black out linings. So, in a very hot spell with the wind from the wrong direction, it might mean having a bedroom at 23C rather than 26C, which would be a massive difference. I know air con is the simple solution but it just feels wrong. Also, on the extremely rare occasions you see a house with one around here, it looks ridiculous!
 
Isn't that really only useful in very dry climates? Because it greatly increases humidity. That's what I've read anyway!

It's called 'evaporative cooling'. It can be very effective, but only if the moist air can be vented fully. It can be tested, by simply soaking towels, and blowing air with a fan, across them. In an enclosed space, it is worse than useless.

They are the basis of many of the cheap, water based, 'air conditioning' gadgets advertised on TV.

A similar gadget, is a leaky water carrier bag, sold for survivalists. The leaks, soak the outer bag, evaporation then cools the drinking water inside the bag.
 
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Isn't that really only useful in very dry climates? Because it greatly increases humidity. That's what I've read anyway!

I'm thinking heat reflecting window film is the best solution so far. I reckon that will keep a house at least three degrees cooler than curtains with black out linings. So, in a very hot spell with the wind from the wrong direction, it might mean having a bedroom at 23C rather than 26C, which would be a massive difference. I know air con is the simple solution but it just feels wrong. Also, on the extremely rare occasions you see a house with one around here, it looks ridiculous!
Nobody says it has to go on the front wall. Plenty of people have allergies and find aircon a life saver.

A bit of humidity is not really an issue when it’s +25 degrees.
 
That's all very interesting. I think 25C upstairs, with two computers, when it's 30C outside is actually pretty good! Maybe the film on the glass really works.

For some reason I'm bothered by it a lot more at night. But today is just a one off so it's not had time really to build up yet. And I've been wearing my summer pants today.
25 degrees is OK but it's the humidity and stale air that starts to make it uncomfortable. Yes the portable air-con is noisy, I can use active NC headphones. After a few hours the bedroom is also comfortable. In the next few days I will see how much all that has cost me in elec!

May be I will venture to a proper air to air unit in a few more years.
 
25 degrees is OK but it's the humidity and stale air that starts to make it uncomfortable. Yes the portable air-con is noisy, I can use active NC headphones. After a few hours the bedroom is also comfortable. In the next few days I will see how much all that has cost me in elec!

May be I will venture to a proper air to air unit in a few more years.

I've been looking at window film. There's so many! I've got very confused and don't understand the ratings at all . What sort have you got, is it visible from outside etc?
 
I've been looking at window film. There's so many! I've got very confused and don't understand the ratings at all . What sort have you got, is it visible from outside etc?
I bought mine from https://www.windowfilm.co.uk/

On the NE facing windows I have used medium reflective silver and on the SW facing windows high reflective silver... https://www.windowfilm.co.uk/buy-online/window-film-by-the-metre/solar-control

Good company to deal with as I have done so on two occasions, first time I used them I DIY'd it on the SW windows with very good result, second time (after I had new windows fitted to house) I got them to do it which cost quite a bit more due to labour. They will send samples to help you make a decision.

Also offers privacy, particularly the high silver: if you're in to naked yoga, you won't scare the local wildlife.

One thing you notice after installation, the inside of the house is a bit darker (obviously!) and it may come as a shock. I am fine about it as I don't mind darker rooms.
 
Quite a few people rubbish portable air conditioners but I bought one earlier this year for the hot spells, but I had a plan. I designed and had made up a sheet of Perspex made to spec to fit over the inside of half of the office window, allowing the air-con duct to attach with little or no leak of the hot air from outside making its way in. Today is the first real test. The outside air temp reached 30C, the office was 25C with a stuffy 65% RH. Within an hour of running the air-con the temp in the office is now 23C and the humidity down to 59%. Yes, the air-con unit is quite noisy but I have active noise cancelling headphones and can happily listen to the First Night of the Proms with no distraction.
I did a very similar thing as your window design only I used 4mm mdf and once the window is opened I manoeuvre it in and put in place of the opener I then hold it in place with window security turns.
So like in the picture imagine the opener being my MDF and I have a turn on each corner. I then designed the hose connection to be a slide fit into the MDF and the whole thing is set up in 1 min. I used the plastic window kit that came with the Unit and modified it and attached it to the MDF
winure.JPG

Yes the unit is noisy and you can not sleep with it, it is used in a bedroom so it goes on an hour or so before bedtime, and from then on it is kept on for a while until you want to fall asleep and then using the remote it is turned to fan only which is much quitter and you can sleep with just the fan, you do need to keep the door shut.
It also can be headed in the living room below so I sit the unit onto a foam mat which takes out the vibration which is where the noise downstairs comes from. But I need some proper foam for the job.
 
I did a very similar thing as your window design only I used 4mm mdf and once the window is opened I manoeuvre it in and put in place of the opener I then hold it in place with window security turns.
So like in the picture imagine the opener being my MDF and I have a turn on each corner. I then designed the hose connection to be a slide fit into the MDF and the whole thing is set up in 1 min. I used the plastic window kit that came with the Unit and modified it and attached it to the MDF
View attachment 350752
Yes the unit is noisy and you can not sleep with it, it is used in a bedroom so it goes on an hour or so before bedtime, and from then on it is kept on for a while until you want to fall asleep and then using the remote it is turned to fan only which is much quitter and you can sleep with just the fan, you do need to keep the door shut.
It also can be headed in the living room below so I sit the unit onto a foam mat which takes out the vibration which is where the noise downstairs comes from. But I need some proper foam for the job.
Nice idea, that may have worked for my window if I made it to fit from the front and slotted in, so to speak. I have two small strips of velcro along the centre gripping mine along with Stormguard E profile draft proofing tape that provides a tight seal and holds the Perspex and hose flange in place.
 
By the time you’ve decided on a solution it will be under 20 degrees again
 
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