double glazing/sealant/condensation

5 replies

KMR281 · 12/12/2011 13:58

hi, our house has what is probably very old (+20y?) double glazing that was here when we moved in. There is very often condensation on the window (not between the glass panels, but on the house side, IYSWIM) in the mornings/through the day. I can wipe it away, but could it be fixed by getting the sealant redone? and if so, is it pricey? I'm wary of getting quotes, cos the DG sales guys are pretty persistant...
Plus, all the window sills on the inside are varnished wood for some reason, and as they have now got a bit damp, it's a total pain - can I just clean, sand down and then paint over with gloss?
thanks in advance.

OP posts:

CointreauVersial · 12/12/2011 14:04

If the seals were gone you'd see misting in between the panels - we have that on a couple of our windows and it's a pain.

If the condensation is on the house side, and not in between the panels, I don't think replacing the sealant would help you - it's down to inadequate ventilation in the house.

Yes, you can re-do the sills as described, but make sure they are dry before you paint them.

Original poster

KMR281 · 12/12/2011 14:16

thanks - we do keep windows open through the night a bit, but condensation still happens. However, good to hear that it's likely not the seals that are at fault. I had thought that the seal between the window and the frame was perishing, and at the corners too, but perhaps it is the lack of vents in the frames (they are that old) that is causing the problem then.

OP posts:

BananaPie · 12/12/2011 19:50

It's probably also because the double glazing is old and inefficient - if the inner pane of glass gets cold (i.e from the cold air outside the house) any moisture in the air inside the house will condense on it. We had our ancient double glazing replaced with modern stuff and no longer get this problem despite identical levels of ventilation.

Original poster

KMR281 · 14/12/2011 15:09

ah well, unless we win the lottery, will just keep wiping up the condensation. thanks for the responses.

OP posts:

PigletJohn · 14/12/2011 22:06

improving ventilation will reduce condensation by letting more of the warm damp air out.

using the extractor fan in the bathroom with the door and window shut will remove the water vapour from bath, showers and wet towels.

The biggest cause of condensation in UK houses is draping wet washing around the house and over radiators.

Flip