Condensation on and in new window

[foreverchanges]

2 months ago I had new windows fitted in kitchen and bathroom and a new back door with glazing that opens into the kitchen. Now the weather has got colder I've noticed condensation on the new windows and door and even when I wipe it off it soon recurs and I can see it glistening where the rubber seal meets the glass.

I've read elsewhere that this is normal though I didn't expect it - I've had trickle vents open all the time and as I live alone I don't generate much steam.

However I'm concerned that after only 2 months there appears to be condensation on the inside of one of the glazed units in my bathroom, photo attached. So does the unit need replacing or the whole window? I wondered if water from the condensation could have weakened the rubber seal but it shouldn't have been able to get in anyway should it as the unit is supposed to be a vacuum so is it a manufacturing fault?

 

[Jurassicspark]

Perfectly normal and suggests that your windows are working fine.

You need to reduce humidity and increase ventilation. Open the windows regularly throughout the day to ventilate the room.

You mention the bathroom window is collecting condensation, do you have an extractor fan fitted? Showering withoit using the extractor fan will cause a lot of condensation.

 

[Harry Bloomfield]

If the condensation is definitely between the panes - check by wiping both outer faces, then you need to get the installer back. You are correct, that condensation can form, on the ousides of either inner or outer panes.

 

[foreverchanges]

Surely condensation on the inside of double glazing isn't normal? I thought it was called 'blown' when that happens as it's supposed to be a vacuum?

I have trickle vents open already and I don't use the shower as I use the one in the gym every day. As I live alone I don't generate much steam in the kitchen just a few boiled kettles a day and occasionally boiling water.

 

[Harry Bloomfield]

Surely condensation on the inside of double glazing isn't normal? I

Between the panes, no, but it can happen on either outer face, despite vents. Moisture always condenses out, on the coldest surfaces of a room, in most homes, that will always be the windows, especially so, when it is cold outside.

 

[aveatry]

Surely condensation on the inside of double glazing isn't normal? I thought it was called 'blown' when that happens as it's supposed to be a vacuum?

I have trickle vents open already and I don't use the shower as I use the one in the gym every day. As I live alone I don't generate much steam in the kitchen just a few boiled kettles a day and occasionally boiling water.

Yes if it is on the inside, between the panes - its blown, as Harry said you need to get them back and just replace the glass unit.

 

[RandomGrinch]

Surely condensation on the inside of double glazing isn't normal? I thought it was called 'blown' when that happens as it's supposed to be a vacuum?

As above, it's not normal for moisture between the panes. The gap is usually filled with an argon mix, rather than having a vacuum.

@Jurassicspark may also be mixing concepts - very high performance, new double glazing may have condensation form on the exterior face of the double glazing - it's a sign that the unit is performing well; there would be no condensation on the interior glass pane.
It's an interesting phenomenon - I was walking past a block of PassivHaus earlier this morning; every window was covered in condensation on the outside.

 

[aveatry]

As above, it's not normal for moisture between the panes. The gap is usually filled with an argon mix, rather than having a vacuum.

@Jurassicspark may also be mixing concepts - very high performance, new double glazing may have condensation form on the exterior face of the double glazing - it's a sign that the unit is performing well; there would be no condensation on the interior glass pane.
It's an interesting phenomenon - I was walking past a block of PassivHaus earlier this morning; every window was covered in condensation on the outside.

Yep I replaced a few to the latest spec and the condensation forms on the outside - then freezes - you can not see out !

 

[Jurassicspark]

very high performance, new double glazing may have condensation form on the exterior face of the double glazing - it's a sign that the unit is performing well; there would be no condensation on the interior glass pane.

If the home is not being heated properly or the interior temperature is significantly lower due to heating being off with windows opened than the outside temperature then condensation can occur on the interior glass surface, even with new double glazing.

Don't ask me how I know

 

[crank39]

As Random G says, with high performance glass units expect condensation on the outside, it proves the inner and outer pane are totally separated from eachother and your not losing heat through the glass warming up the outer pane

Condensation within the unit then it's a faulty unit, it's blown, shouldn't happen but it can, I change blown units in new builds every week.

Condensation on the room side, definitely something going on there and shouldn't be happening as it's a reverse of why the outer pane remains cold compared to the inner pane, check the unit hasn't been fitted back to front, the inner pane should be the clear glass and the patterned pane should be the outer. If all that is ok then I'd have to question the amount of humidity your creating, it's a bathroom so it's normal to create more in this room than any other but still do you ventilate when be bathing or taking a shower, is there an extractor fan in the bathroom, do you open the window slightly, depending on the dew point (that's the temperature in which vapour turns back to a liquid) if that surface reaches dew point then water vapour will condensate on it, I would take a wild guess and say your bathroom is a cold room but you take a shower and create steam and then it condensates on the cold glass, if the room and glass was warm and above the dew point then water vapour cannot condensate on it, it will remain a vapour

Ooooo that was long winded

 

[foreverchanges]

The condensation is only on the bottom inch or so of each glazing unit if that makes any difference. So in the case of window with condensation between the panes, is that a manufacturing fault or could the problem have been caused during installation?

 

[crank39]

Likely a manufacturing fault.

To answer some of your other questions re the vacuum, it's very very rare that units have a vacuum, they used to exist way back but as far as I'm aware 99.9% are not nowadays, @ronniecabers is your man, a unit manufacturer so he'll be better placed to answer that.

Argon, yes whilst brilliant when it's in the unit but what DG salesman won't tell you is that by around 4 to 5 years it's all leaked out anyway, whilst technically it's a sealed unit the seal is still permeable, argon WILL deep through it, again maybe Ronnie can confirm this

 

[foreverchanges]

I live alone so I don't generate much water vapour I don't think. I use shower in the gym so it's breathing, washing up a couple of times a week, and wash and shave on a morning, kettles a few times a day, pans on a few times a week and houseplants that generate it.. I don't have central heating on much as it's expensive, to put it on just because of condensation seems ridiculous when I basically live in my living room where I've a gas fire.

 

[crank39]

It looks like you know what the main culprits are for creating moisture but yeah its showering/bathing, cooking especially with gas as thats a wet heat, boiling a kettle, even house plants create moisture, drying clothes indoors couple that with poor ventilation and you've got the perfect enviroment that causes condensation

 

[RandomGrinch]

. I don't have central heating on much as it's expensive, to put it on just because of condensation seems ridiculous when I basically live in my living room where I've a gas fire.

Well, that goes a way to explain things.
If the house isn't warmed evenly by C/H, there will be more cold areas where condensation forms.
Burning natural gas in a fireplace also produces moisture - about 1.6kg of H2O per cubic meter of methane consumed.