How to keep attic room cool in the summer

[terminal7]

AC is not an option given configuration of the roof. Have tried ordinary fans - but little effect last summer. Wondered if the Dyson is effective - varying reports.

The room heats up during the day - despite blinds being down and windows open. By sunset temps can reach 35C plus.

Any suggestions welcome.

T7

[monabri]

Mobile AC unit with exhaust pipe dangling out of the window.

[Mike4]

AC is not an option given configuration of the roof.

How so?

You can have a floor-standing interior unit, looking rather like a flashy storage radiator. These actually work very well IME.

[monabri]

AC is not an option given configuration of the roof. Have tried ordinary fans - but little effect last summer. Wondered if the Dyson is effective - varying reports.

The room heats up during the day - despite blinds being down and windows open. By sunset temps can reach 35C plus.

Any suggestions welcome.

T7

I can't see any Dyson model that would remotely make a worthwhile difference ...

[DrFfybes]

There's little can be done to stop it warming up from the Sun, but you can minise it and try and cool it once it goes dark...

Keep the door closed to prevent the rest of the house heat going up during the day, otherwise blinds closed and windows vented but perhaps not fully open as the roof tiles can heat the air around them and that can get in and make things worse.

Then, as it goes cooler try and get a cross draught with a fan between 2 windows to draw cooler air in, or open the door and windows and as the hot air escapes it will draw cooler downstairs air in.

Paul

[Lootman]

I had reasonable success with two circular fan units built into the roof, blowing the hot air out. The fans came on automatically once the temperature reached a certain point, i.e. it was controlled by a thermostat.

[kempiejon]

six litres of water the six kilograms of water evaporating takes away the same amount of heat as a 12 000 btu air conditioner why do you think grass is cool

https://www.youtube.com/watch?v=5ngNskZGcD8

[terminal7]

AC is not an option given configuration of the roof.

How so?

You can have a floor-standing interior unit, looking rather like a flashy storage radiator. These actually work very well IME.

Mike4

Doesn't the interior unit need to be 'attached' to an external unit?

T7

[9873210]

How so?

You can have a floor-standing interior unit, looking rather like a flashy storage radiator. These actually work very well IME.

Mike4

Doesn't the interior unit need to be 'attached' to an external unit?

T7

The "outside" unit can get access to the outside air using a snorkel (with separate feed and return air paths). Only the vents on the end of the snorkel need to be actually outside. In this type of unit the mechanicals are in a single box with a pipe similar to a drier vent going through a wall or window.
This is similar to a modern boiler with air feed and exhaust pipes, the combustion chamber uses only outside air. Because of the lower temperature and lack of combustion the A/C unit can use far flimsier air pipes, which makes instillation easier. To be fair the A/C needs more air volume than a boiler so the vent diameter will be bigger.

I assume the OP has ruled out the solutions of better insulation and air sealing, painting the roof white, and ventilating any roof space outside the room.

[88V8]

The room heats up during the day - despite blinds being down and windows open. By sunset temps can reach 35C plus.
Any suggestions welcome.

Hatch... make a hatch or hatches in the roof with automatic openers that will let the heat out.
Greenhouse (wax) openers would de minimis do the job. Better still if a low window is open to create more circulation.

I did this when I had a conservatory built on our previous house. Makes a huge difference. And consumes no electricity.
Four hatches....



V8

[Mike4]

How so?

You can have a floor-standing interior unit, looking rather like a flashy storage radiator. These actually work very well IME.

Mike4

Doesn't the interior unit need to be 'attached' to an external unit?

T7

Yes it does, with two thin copper tubes which can be tens of metres long.

Again I ask, why/how does the roof configuration affect anything?

[UncleEbenezer]

My attic room gets hot in summer, but is improved by one of these on the south-facing Velux window. Lets light through, but keeps quite a lot of heat off (they claim 78%).

More expensive options have controls that can be operated electrically from inside the room. Mine can't, and needs to be manually opened/closed. So I just do it once a year, about now and around the end of September as the risk of uncomfortably-hot alternates with that of getting chilly.

[Sobraon]

Solar panels will shield the roof and keep it cooler (5 deg ish cooler - but I haven't seen the research for this assertion) and use the generation from the panels to drive a portable AC unit.

[terminal7]

Everyone - thank you. A lot to think about. Just when I get a little fed up with the rather tedious bipartisan and hackneyed 'debates' on a couple of political topics, a bunch of Fools come along and remind me of the positive side of TLF.

T7

[DrFfybes]

I did this when I had a conservatory built on our previous house. Makes a huge difference. And consumes no electricity.
Four hatches....



V8

Can you heat it with candles in Winter, and of so how many?

[jaizan]

Keep the door closed to prevent the rest of the house heat going up during the day, otherwise blinds closed and windows vented but perhaps not fully open as the roof tiles can heat the air around them and that can get in and make things worse.

Then, as it goes cooler try and get a cross draught with a fan between 2 windows to draw cooler air in, or open the door and windows and as the hot air escapes it will draw cooler downstairs air in.

I don't have a loft room, but the air temperature in my loft reaches 50C on a sunny summer day, despite there being a LOT of insulation between that and the rest of the house.
So it still gets uncomfortably warm despite no heat input from the house below.

Insulating the rafter area seems to be the way forward for a loft room.
Combined with some ventilation.

Also, installing solar panels ought to help, as they will shade the roof tiles. If that's still not enough, use some of that solar energy to power aircon.

[Mike4]

Or, along similar lines but more extreme, change the roof tiles for thatch!

The thatched roof keeps my hovel wonderfully cool upstairs in summer. Although I still have a small aircon installation for the stinking hot summer nights we seem to get nowadays.

[88V8]

I did this when I had a conservatory built on our previous house. Makes a huge difference.
Four hatches....

Can you heat it with candles in Winter, and of so how many?

Less than five, if they're large ones.

V8

[DrFfybes]

Can you heat it with candles in Winter, and of so how many?

Less than five, if they're large ones.

V8

"Less Than?"

Sheesh.

Paul (reading a new book about Which Tyler, the Founder of the Pedants Revolt)

[Watis]

Less than five, if they're large ones.

V8

"Less Than?"

Sheesh.

Paul (reading a new book about Which Tyler, the Founder of the Pedants Revolt)

* Pedants', surely?

Watis