[Closed] Blown double-glazing (bodgetastic DIY question!...)

The reason why they have failed is because they have a hole somewhere so drilling a new one probably won't make things any better.

Try finding someone local who makes replacment DB glass to order. I got a 900 by 500 12mm unit made to order for £12 and the place I got it from gave me loads of good advice on how to fit it.

Other than unsightly condensation, is it actually a problem?

(I ask because I've got a couple, and fixed it using the time honoured approach of ignoring it.)

They don't have one hole, they have hundreds of tiny holes designed to allow changes in atmospheric pressure to equalise, preventing the panes from being stressed inwards or outwards. Moisture flows in, condenses and cant get out and eventually the silica gel left inside becomes saturated.

Like you I enjoy a DIY challenge and as a short-term fix I'd be tempted to try drilling top and bottom into the separator and blowing dry air through or topping up the silica gel. This might work better on a warm day when more moisture is in evaporation. In the end you will need new units, which is a job for a good local glazier once you've negotiated the price and spec. Ask about inert gas filling to improve thermal performance.

[i]they have hundreds of tiny holes designed to allow changes in atmospheric pressure to equalise[/i]

[i]
Ask about inert gas filling to improve thermal performance. [/i]

I assume the inert gas ones are sealed, though?

[b]They don't have one hole, they have hundreds of tiny holes designed to allow changes in atmospheric pressure to equalise,[/b] preventing the panes from being stressed inwards or outwards. Moisture flows in, condenses and cant get out and eventually the silica gel left inside becomes saturated.

Like you I enjoy a DIY challenge and as a short-term fix I'd be tempted to try drilling top and bottom into the separator and blowing dry air through. This might work better on a warm day when more moisture is in evaporation. In the end you will need new units, which is a job for a good local glazier once you've negotiated the price and spec. Ask about [b]inert gas filling to improve thermal performance.[/b]

1) surely one big hole is as good as lots of small ones.
2) surely if there was a hole, the inert gas would get expelled fairly promptly byt he heating and cooling effect (which is far greater than changes in atmospheric pressure).

Pretty sure they're sealed and only get condensation when the seal breaks.

They should be sealed. It's why ones with a catflap hole in are really expensive :grr:

But standard ones really don't cost much - get a couple of quotes - it'll almost certainly be cheaper than you think.

Or...

http://mymistywindowfix.com/steps-1-3.php

Drill a hole, chuck in a load of slica gel, gaffer tape hole up, jobsagoodun.

I could we way off on this but if you feel like trying a bodge, would you not be better off taking the DG unit out, drying the condensation out and resealing the bit that holds the 2 pieces of glass together? Some kind of tape/silicone/bitumen product may work.

[i]Pretty sure they're sealed and only get condensation when the seal breaks.[/i]

Indeed they are sealed. Can't think who told someone they had loads of tiny holes...must have been a wind up! The better sealed units have a flexible silicon type putty which doesn't dry out and last a long time. Due to the big temp changes, vacuums are created which at times suck in air through the tiniest holes which contains moisture. Drilling a hole will not send this moisture back out again, unless you drill lots of holes, but you'd be left with a badly stained internal unit.

Therefore, save your money and get quotes for replacement units.

don't bodge it, these are expensive things that you will ruin.

I use a local firm who come along and dismantle your existing window and then reseal it using the same major components (like frame, glass etc) with a few new bits like sealant so they essentially service rather than replace. We've done circa 7 or 8 windows over the last few years and they really are good as new.

Much cheaper option. I'm in Surrey, shout if you are nearby and I will share the details. If not then I'm sure you can find a similar resource locally.

don't bodge it, these are expensive things that you will ruin.

Well, they're not really. IIRC I paid £30 for a reasonably large window sealed unit. The OP isn't talking about doing anything to the frame which is the expensive part.

They are really not that expensive, nor are they difficult to fit.

Either ignore it, or fix it properly.

drilling glass?

Some double glazing spacers with thousands of holes, yesterday:

[img] [/img]

(I was told that not matter how good the build, damp air goes in and out through the corners and through those holes and eventually saturates the dessicant, which is contained inside the spacers)

The holes are to allow access to the dessicant, not to the outside air.

Right as I used to make these things for a living. I feel qualified for once.

The units are sealed with a black bitumen, holes are inside to allow moisture in the unit into the dessicant.

If I were you id buy a good stanley knife, some window blades and break the units down. Strip the glass off take them to your local glass place and get them re beaded.

http://www.christieglass.com/pricecalculator.php

I used this random firms online calculator to give an idea of price. My local glazing company was actually cheaper and there are plenty of YouTube videos showing you how to replace a glass unit. Just depends how handy / brave you are.

If you go down the getting quotes route give Melvin a ring at Windows 2000 in Ripley 01773 747080

Some double glazing spacers with thousands of holes, yesterday:

(I was told that not matter how good the build, damp air goes in and out through the corners and through those holes and eventually saturates the dessicant, which is contained inside the spacers)

I'm afraid you were told wrong. New double glazed units will be fully sealed. Like everything, this has a finite life. In the case of mine (I made around 6000 windows last year and had almost as much roofing glass) this takes at least 10 years. Anything under that and I replace foc. Uv light and water can increase the speed of breakdown, so best to stop that from getting to the bitumen used to seal them. Most of my units come from Pilkington in Derby, so will be pretty industry standard. Same applies whether Argon or Crypton filled and whatever solar control / low e coating is on the glass. The desiccant is to ensure that any trapped moisture when the units are sealed doesn't cause condensation.

OP, replacement glass is best (easy with wooden windows) some companies will do what you're suggesting, then spray an anti mist coating on the inside of the unit which prevents reoccurrence before plugging the holes. No idea how effective though!

I replaced a blown unit last week cost just under £17 easy as pie to fit, link below should give you an idea of cost

http://www.hgwsolutions.co.uk/custom-made/double-glazed-windows.html

Does the same manufacturing process apply to the units used in wooden frames too?

Rogerthecat, all my windows are wooden so yes to the glass units, mostly the sme from the same places. Specs may be different but as long as argon filled as min, they will be sealed.