Condensation

Soldato
Joined
24 May 2009
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North East
Hi chaps.

Just recently bought a new house and a couple of the rooms get really bad condensation. Any reasons why this might be?
 
Warm humid air (baths/showers/drying clothes indoors/breathing) touching cooler outside walls and windows. Ventilate the rooms more and/or move furniture away from outside walls.
 
Is it cheap windows that can cause this the temperature bridging thing?

Older metal windows tend to do this. We rented a flat which was half metal and half plastic, the rooms with plastic never had condensation issues but the rooms with metal did.

Main culprits are baths/showers with no open window or fan, drying things indoors or lack of ventilation (most double glazed windows have trickle vents, which should be opened).
 
We've got terrible condensation at our place. Had an expensive system put in to help, which it didn't (and ended up moving humid air into the loft, where it now rains). I've resorted to buying trickle vents for the windows in the hope that they will allow the humid air out.
 
Trickle vents may be the thing. The double glazing isn't the newest and doesn't have them. Can you just get them retrofitted into existing double glazing?
 
I hope so! That's what I'm planning to do (I have trickle vents on order). I believe it's a case of drilling a number of holes through the plastic of the frames of the opening windows (on either side of the frame) and then fitting the vent over the top. Will report back my findings as i'll probably do this next weekend if the vents are delivered.
 
I hope so! That's what I'm planning to do (I have trickle vents on order). I believe it's a case of drilling a number of holes through the plastic of the frames of the opening windows (on either side of the frame) and then fitting the vent over the top. Will report back my findings as i'll probably do this next weekend if the vents are delivered.

Cheers mate, I'll keep an eye on this thread for an update :)
 
Yes you can retrofit trickle vents. They just require a slot cutting into the sash and then the vents are attached by screws.

If it was me i'd just open a window and lock it on the night vent position. Downstairs windows will obviously need fully shutting at night, but you don't need 24/7 ventilation as long as you ventilate the room at some point during the day it will help.
 
We have the same issue in our smallest bedroom (boxroom) , the condensation in there is horrific, running down the windows, running down the walls, furniture/bedding/clothing which is near the walls become utterly soaked by morning. Not really too sure what to do to combat it. 2 of the bedroom walls are external walls (semi detached house), the double glazed window in there is quite old (maybe 20 years) , and it has no trickle vents. Would trickle vents be enough to combat such strong condensation? The window is opened from time to time, but in this weather its difficult to have the window open without turning the room into an icebox.

Its only a small bedroom, but the kid (18 yr old) is in there, usually with his girlfriend of a night, so 2 people, big screen tv, double bed etc, so the room is quite crammed too.
 
We have the same issue in our smallest bedroom (boxroom) , the condensation in there is horrific, running down the windows, running down the walls, furniture/bedding/clothing which is near the walls become utterly soaked by morning. Not really too sure what to do to combat it. 2 of the bedroom walls are external walls (semi detached house), the double glazed window in there is quite old (maybe 20 years) , and it has no trickle vents. Would trickle vents be enough to combat such strong condensation? The window is opened from time to time, but in this weather its difficult to have the window open without turning the room into an icebox.

Its only a small bedroom, but the kid (18 yr old) is in there, usually with his girlfriend of a night, so 2 people, big screen tv, double bed etc, so the room is quite crammed too.

We've got two external walls too, definitely helps having the windows cracked open at night (small-ish room, two of us). I doubt trickle vents are as good as this but I want to try as I don't always remember to open the windows every night.
 
We have the same issue in our smallest bedroom (boxroom) , the condensation in there is horrific, running down the windows, running down the walls, furniture/bedding/clothing which is near the walls become utterly soaked by morning. Not really too sure what to do to combat it. 2 of the bedroom walls are external walls (semi detached house), the double glazed window in there is quite old (maybe 20 years) , and it has no trickle vents. Would trickle vents be enough to combat such strong condensation? The window is opened from time to time, but in this weather its difficult to have the window open without turning the room into an icebox.

Its only a small bedroom, but the kid (18 yr old) is in there, usually with his girlfriend of a night, so 2 people, big screen tv, double bed etc, so the room is quite crammed too.

Sounds like the room I'm in. I've got a window on both exterior walls, and leaving them open barely enough that you can tell seems to help a lot. Then crack them wide open for half an hour in the morning.

What's the heating like in the room? I just got used to accepting having the windows open and being cold if it reduced the condensation. Relative humidity should decrease with heat (in theory), so a few days running full whack with a de-humidifier might soothe the problem.
 
Most annoying catch-22 situation.

Don't want to lose all that expensive heat you are creating? Insulate.
Don't want condensation? Open up windows/vents and let all that expensive heat escape.

Arg!
 
Trickle vents may be the thing. The double glazing isn't the newest and doesn't have them. Can you just get them retrofitted into existing double glazing?

Yeah, drill one side, screw on vents, drill other side, screw on vents. It's just holes in the frame with some flappy bits over the top. If you can leave your windows open a crack (lots of them you can) then just do that.

Also, if you're drying clothes indoors. Don't. Seriously, a load of washing will basically evaporate a hell of a lot of water into the atmosphere (If you've ever emptied the tank on a condenser drier, you'll know what I mean, half a pint on average per load I would say), where is it to go?

If you buy an older house, you will always get some damp. They weren't built for double glazing and modern life - they were build to have air circulating, and breathe, like with the old slightly drafty single glazing. People "modernise" these houses and you always hit problems.
 
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What's the heating like in the room? I just got used to accepting having the windows open and being cold if it reduced the condensation. Relative humidity should decrease with heat (in theory), so a few days running full whack with a de-humidifier might soothe the problem.

Its got a small radiator in it, not usually on as the warmth in the room from 2 people and the furniture and the large wall mounted TV all generates enough heat that there is no need for the radiator
 
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