Bad condensation on inside of double glazed windows Post questions and find answers on glazing, double glazing, upvc glazing, conservatory glazing, fixtures and fittings etc....

[Ipswich1971]

Hi,

Everyday during winter I have bad condensation on all my windows, obviously much worse on bedroom windows but downstairs are also badly effected. There is also condensation on the frames, plastic trim surround and the walls next to trim wet to touch (thermal bridging?). I was never overly happy with the quality and fitting of them over 10 years ago but local fitter washed their hands and I ended up dealing with the manufacture to resolve poor hinges and drafts etc. Please see the photos, would new windows resolve this issue or do I just have a humid house. Detached house built about 1968 with cavity wall insulation. Your opinions would be most appreciated.

[stoneyboy]

Hi ipswich1971
Suggest you open your windows every day - especially the bedroom windows. When you close the windows see if there is a night vent position they can be locked in.
If this is unacceptable you will have to get trickle vents fitted in all window frames.
Regards S

[Ipswich1971]

Hi stoneyboy,

Thank you for your reply, really appreciate the feedback. We karcher vacuum the windows every morning and then open the windows for at least an hour to vent or turn on a dehumidifier for an hour or so if damper outside than in. I have considered trickle vents but do not like the idea of all the heat and energy in the house disappearing outside. I do not see the same issue on any of our neighbours houses of all the same type and with the walls being damp/wet around the side and top of the sill I wondered if the windows were badly fitted. We do not put damp clothes in the room either. It just seems an awful amount of condensation considering these are double glazed units.

[stoneyboy]

Hi ipswich1971
Thanks for the further details, certainly it looks like you have an abnormally large amount of condensation in your house.
It is unlikely that even if the windows were badly fitted it would cause this problem. Do your neighbours have trickle vents in their windows? Presumably all those things that should vent outside do so eg hob extractor, bathroom extractor, tumble dryer ....
Suggest you run the de-humidifier 24/7 if it’s working correctly it should be pulling out 1-2 litres per day.
Regards S

[Ipswich1971]

Hi S,
Neighbours don't have trickle vents that I can see. Extractor fan is always on when cooking and kitchen door always shut, bathroom window always open after/during everyone has a shower and then for some time after, bathroom door always shut too. Tumble dryer is a condensing one so its self draining. The house has cavity wall insulation (old foam style) and the loft has the recommended, maybe slightly more, insulation. When the windows were fitted there were drafts coming in from 'around' the frame edges and into the rooms, fitter rectified with foam. The window seals had drafts (the curtains would move in the wind) rectified with new hinges and rubber seals. The larger opening windows do not open and close correctly anymore, you need a knack to get them to close level and sealed by open and closing with a bit of force and wiggling. They're not the best :-(

[stoneyboy]

Hi ipswich1971
You have all the right things in place, try running the dehumidifier continuously.
Regards S

[B4Less]

Hi, This is a ventilation issue. I would suggest installing wall vents or some sort of Heat Recovery Ventilation Unit (HRV). There are many on the market, with Brink being a good starting point. Install this, and you will never look back. If that is not an issue, you will need to install cross-ventilation in each room. this will allow for the replenishment of air in the room. What is happening is that air is becoming stagnant in each room. Then condensation on cold surfaces like windows and cold walls. After you do that or at the same time, maybe look at the insulation level you have. Your walls are getting cold due to a lack of insulation, so if you can fix that, you should not have an issue after that. First things first though is to get in HRV. As a temp fix until that is done get a fan and turn it on blowing air around the room and out of the room. This will force the air to move on. You may need a fan in each room with the issue, but over a few weeks, this will dry out the room and make it feel warmer.
Regards,
Build4less