New DG windows and condensation INSIDE

Andrea15

We have had our new super duper windows instlled just before Christmas. Everything is fine except that when outside is cold, say below 0°, there is condensation on the INSIDE of the window. There is actually quite a lot of condensation, as we have a pool of water on the wooden window sill.
The guy is supposed to get in touch with us next week, but in the meantime I wouldn't mind some advice.

Note:
-The vents are all open and we open the windows now and again to let air in.
-This is a dormer window that had to be completely rebuilt (nothing strange with that, the opening is such that you have to do it when you change windows)
-This is a Planitherm (sp?) glass with Veko (sp?) frames.
- now and again we have (very little( condensation on the OUTSIDE too, but that I am told is normal.

Aylesbury_Duck

If it's inside the glazed unit itself, then the unit is faulty. As the condensation is on the inside of the window, then there is no fault with the window and the problem is your lifestyle generating excess moisture. It's probably the coldest surface around so where the moisture will condense at low temperatures. First step is to reduce moisture generated by showers, cooking, etc. Second step is to ensure that there is airflow (sounds as if you're doing that already), third step is to ensure the room concerned is adequately heated and finally, if the problem persists, consider a dehumidifier.

Andrea15

The moisture is on the inside of the room, not between the panes, so the unit is not faulty.

With the old windows we had SOME moisture, but not loads. I would have thought that the new ones would improve the situation, rather than decreasing it.
Being a bedroom with no en-suite, there is no much cooking/showering taking place in the vicinity
The room is heated as much as it is confortable at night (i.e. not at all). Maybe the problem is the think curtains? But the vents open should take care of that.

-taff

if it's a bedroom, you are breathing in and out all night which will cause quite a bit of moisture.
I have it on my bedroom windows, and it's a direct result of us breathing in there in the night because inner surface is cold, and the moisture condenses there, we also have thick curtains. However, it's not that bad, and I could open the windows to increase the airflow but am not going to in this weather.
You can get some stuff to put on the windowsills to soak the moisture up if it's really bad, but unless you have excellent ventilation or you stop breathing, the issue will not be going away. It all depends on what you want to do, whether stop it entirely or minimise it.

Andrea15

Well, here is a pic I took the other day:
https://photos.app.goo.gl/Yw5YfKwS1PhkEHXdA
Now it has dried up and has left a stain (OK, we haven't treated the wood yet).

Loanranger

Do you sleep with your windows open? If not, you need to do this. If you have at least a 7 tog duvet you will be warm enough in bed. I speak from experience.

Andrea15

No. the window is closed, but the vents are all open.
And what is the point of keeping the windows open when it is freezin cold? I might as well have kept the old windows, then...

Aylesbury_Duck

It's lifestyle, some of which (like breathing!) you can't change. You have warm moist air in the room which has to condense somewhere when the room is cool. There's no reason for new windows to have made the situation worse, unless the new vents aren't as good as the old ones, perhaps?

As has been said, your solutions are to leave the windows open to improve ventilation or to deal with the problem reactively, ie with dehumidifying products.

-taff

Andrea15 wrote: »

No. the window is closed, but the vents are all open.
And what is the point of keeping the windows open when it is freezin cold? I might as well have kept the old windows, then...

well, not really, it just means your old windows had more ventilation than the new ones, and that probably means they had it all the time, rather than just in the cold weather.
Almost unrelated but I was wondering has anyone got triple glazed windows here? And do they have less condensation?

paddy's_mum

I have a Karcher window vac and every morning when I open my thick curtains and look at what the weather is doing (in the same breath as it were) I check if there is any/much condensation on the inside of the window.

If there is, I vac it up. Problem solved.

neilmcl

Try and get as much air flow in the bedroom as possible, leave your door open and the curtains slightly ajar. Also when you get up open the windows.