Condensation between panes of DG glass in windows

[whataboutbob]

I have a 1960s ex local authority flat (rented to students) and in 2 rooms there are droplets of condensation in between the 2 panes of glass. Can anything be done short of replacing all the windows? Also, does it mean that the DG insulation is less effective? Thank you.

It means it's not airtight, so yes, the insulation will be less effective

Don't think you can do anything other than replace. I can't see how you'd be able to create a vacuum again and reseal.

Have you come across Cloudy2Clear? Sorry haven't used them myself so can't recommend but you could Google for reviews.

Unfortunately this does happen after some years. Our house was built in 1996 and we have a few windows where the seal has started to decay. They will need replacing.

We have just the glass replaced before by a glazier. Much cheaper than replacing all the window.

I meant just the glass, not the whole window. We have had some replaced already, but a few more are beginning to go now.

The window has blown, you can have the glass replaced.

Just a question- as the property suffers from condensation, would making the double glazing airtight worsen the condensation ?

The seal has gone, most glaziers can replace the seal. It isn't the glass that's the problem but the seal.

Yes. You need ventilation to deal with condensation. Our windows have trickle vents and we don't suffer from condensation - nor do I dry washing indoors without either opening a window or using a dehumidifier.

People vastly underestimate just how much moisture is in a machine load of washing. When I tumble dry washing I get several pints of water in the reservoir. If you dry washing in the house without ventilation you end up with condensation.

Thanks, this is all very useful. I have invested in a vented tumble dryer for the flat due to condensation . There are trickle vents but I suspect the students close them. Whenever I’ve dropped in/ passed by the windows have all been closed.
Good to know a glazier could fix the seals.

My parents had to do this with four windows that were put in the 60s. All had to be replaced. They had fungi growing inside them too and the rooms were damp. They got upvc replacements and what a difference. Rooms are now damp free and insulated properly

We've had a few panes replaced recently. Think an opening side window was around £60 and a main window (large) about £80.

Thanks guys, I am somewhat reassured at the prices, they don't seem too bad. Re: condensation, as I understand it, it occurs when steam hits a cold surface, and is worse if you don't have adequate ventilation.
I'm doing a condensation cost: benefit analysis in my head and wondering if improving the double glazing will improve or worsen the situation. Good to hear it made things better in your parents' case Bamboo. PigletJohn if you are out there, what's your opinion??!!

We had the same thing in a 1960s house. It is quite common in older DG and is supposedly down to the effects of the sun gradually heating the air between the panes. The repairman told me that south-facing windows are usually worse affected. We had the misted units individually replaced by a window repair company. It wasn't as expensive as I thought it would be. They just popped the old units out and inserted the new one in a matter of minutes. We did find that once one unit had misted, the others followed suit over the next couple of years so we ended up getting most of them replaced eventually.

Thanks wizziwig. Did you notice whether it made any difference to damp/ condensation levels in the room?

I hadn't noticed a particular damp or condensation problem in the house, it just seemed to be something that happened to the windows in isolation. Repairman told me it was common in windows of a certain age. If anything, I would say that we had condensation in the winter when the heating was on, but the misting of the glass seemed to worsen in summer (or perhaps was more noticeable because it was daylight for longer!).

Thinking about it, one of the windows we didn't have to replace was actually the bathroom one, which was subjected to the most moisture, so I don't think the misting is necessarily related to dampness within a room.

It's an extremely simple job to have the glass replaced, there are usually a few companies advertising in the local papers. They measure up, quote the price and fit them in minutes a few weeks later.

We put it off for ages until we had a few needing to be done, and were surprised by how reasonable it was. It was the windows on the sunny side of the house that went first.

Changing the glass will not affect condensation.

If the people inside throw buckets of water at the walls, or drape wet washing indoors which amounts to the same thing, how will the water get out?

Open windows, extractor fans and trickle vents can all take water vapour out of a home, but if the occupiers add water faster than it is removed, it will be wet.

Thanks piglet John. I know they are draping wet stuff over a maiden in the kitchen, they maintain they are not drying in the bedrooms.
Would replacing the window panes make a difference to the insulation in the rooms ie keep them warmer? Or does it boil down to cosmetics?

No, it will just make the windows look clearer.

There are some people who have an aversion to ventilation, and there are some people who insist on draping wet washing indoors.

There does not seem to be a way to change their minds.

If the bathroom has an effective extractor fan, washing can be hung over the bath with the extractor running and the door and window CLOSED. It will prevent the water vapour diffusing throughout the flat.

Thanks Piglet. If it's just cosmetic I won't rush to get the panes changed.
I suspect the extractor fan in the bathroom is quite weedy and I am thinking of getting it changed. Do you know what type/ make would be best? Also, who installs it- an electrician?

often an electrician because (remembering that people who have an aversion to ventilation will not turn it on) they are best wired into the room light, so they come on when the light does, and run on for (say) 20 minutes afterwards.

If it's a simple 4-inch through the wall fan, this one is a good make, and extremely quiet. I use this range. It will run for 125 hours on about 12pence worth of electricity. I don't understand sound measurement, but you can look up a table somewhere to see what 26.5 dB equates to. It is IP45 rated so can be used above a bath, and has a ball-bearing motor so likely to last a long time. Has its own backdraught shutter. It is more expensive than a cheap fan, nut better. If you are near a branch of this supplier, they will probably deliver free. There may be a similar electrical supplier in your town.

80 m3/hr is about as much as you can get from a 4-inch (100mm) wall fan (the most common size) so it needs to run whenever the bathroom is occupied. If you have a ducted fan accessible above the ceiling, you can fit an inline fan that can be more powerful, but they are a bit big.

nut = but