Blown double glazing DIY success

Well there is that yes!

Too much sawdust in the sausage?

Er it would be if you "Did It Yourself"...

If going to that trouble just replace the DG unit...

Did you do the holes on the inside?

A relative had this done on a large unit & I'm sure they drilled from the outside & then fitted some sort of clear "grommet" that could allow air & moisture etc in & out.... any idea where I can get some of these grommets?

I recently moved into a house I'd just bought. One of the upstairs double glazed windows was full of moisture - it migrated upwards when the sun had been on it and then dribbled down in streaks.

I already had an Aldi/Lidl set of glass/tile drills and I bought a £6 USB aquarium air pump. I drilled a couple of 6mm holes on opposite corners, set the pump going and two sunny days later the moisture is all gone.

Just one thing to note: I'd used a pressure sprayer to cool and lubricate the drill, and have ended up with a streak of ground glass washed down from the top hole, also a slight spray on the opposite side to the holes. I might try finding a small magnet I can use to brush it out of sight.

Good tip.

I suspect it would still have worked, if more slowly, if you had put both holes in bottom corners, and that would have minimised the dribble. IIRC I have also read of people tackling the problem by drilling sideways into the air gap, rather than going through the glass (if you see what I mean)

I hadn't thought of that. Outside air will generally have lower humidity and so even a slow flow top to bottom would eventually clear the glass and prevent further condensation.

I guess as long as any residual flow is small and no rain gets in it sound like a near perfect solution?

Some years ago I did the same, but using a 3mm drill. I hope you drilled from the outside, otherwise warm moist air from inside the house will fill the gap between the panes and on cold nights it will condense. Drilling from the outside means that the air in the cavity always holds less moisture.

Yup, a trigger sprayer was what I used. But I just put up with the dribble marks. With only a 3mm hole, there wasn't much I could do with it anyway.

if the glazing bars are on the inside, would it not have been easier to remove the DG unit and drill through the aluminium? spacer at diagonal corners ?.

Then after drying out (inside), dribble some silica gel into the bottom of the unit and reseal with some silicone ?.

But that isn't 'diy'

Yes - upstairs windows. Didn't fancy having an accident at the moment.

Sorry, no. I'm just going to cover the holes with "book tape" - "invisible" sellotape.

Is anyone making replacement DG units?

Local butcher's which had a smashed window has to cope with it boarded up, as there are no replacements available locally.

Owain

We had a number of failed units (all from Anglian); the rest were a different supplier. All out of warranty and bought by the previous owner of the house.

There's a franchise called Cloudy2Clear that did an excellent job at a reasonable price, and also replace the crap Anglian hinges.

If you look at the aluminium spacer between the gasses, you will notice lots of holes. The spacer is full of dessicant. When the dessicant is expended (ie max moisture)you get the condensation. These double glazed units leak air virtually from day one (and suck it back in) Only the dessicant keeps them clear. (until it's expended)

If pumping fresh air in, use air from the fridge or freezer, virtually zero humidity (ie put your aquarium pump in there while running it)

Remember this cold air will fill the space from the bottom up.

The problem is you can't get rid of the streaks the condensation leaves.

It's only invisible because of its matt surface. On glass it will be very visible. I would try Scotch tape rather than Sellotape which goes gooey and yellow before falling off.

So how are you going to refill the void and seal the holes? I have one unit like you describe but when you think it was put in in 1973, its done very well. A friend says he can see a tiny crack in the outside pane, which is probably where the moisture has crept in. These are the old narrow gap type with solid ally frames in a hardwood surround with no window locks, so yet another job that will need to get done. I'll wait to see if I survive the virus first though!

Brian

More to the point, if it is toughened glass, as it should be if it is a patio door or critical area, then drilling is (or should be?) not possible.

Andrew

The toughened glass thing is fairly recent.

Well, the void is now far, far dryer than it was, so I'll just leave it with whatever air will be in it.

There is still moisture appearing, probably coming from the dessicant. I'll just keep pumping when the sunlight is on it until it stabilises.

At the moment I'm just putting tape over the holes when it's not pumping.

I might put a blob of silicone in eventually.

Certainly, it's in a far better state than it was, it wasn't just a haze, but rivulets running down.

It's probably going to be replaced in the not too distant future, certainly the patio door below it needs replacing and I might as well get both of them done together.