Condensation between double glazing

charlesworth82

Unfortunately, some of my double - glazed windows have condensation inside them. Does anyone have any experience with window doctor-type companies who reckon they can cure this? Any recommendations regarding this technique, or companies who would replace the windows completely, would be most gratefully received (live in leeds). Thank you.

DNK

It can often be fixed without replacing any windows but it's not particularly cheap I don't think and I don't remember seeing any DIY fixes for it but there might be.
I looked into it ages ago when my windows had the same problem but I was looking to replace them anyway despite of the problem as they were old and looked naff.
How old are your windows, I suppose they're well out of their guarantee period?

charlesworth82

have lived there a few years and they were already in when i moved in. Will it cause much problem as the window is covered by blinds at all times so it isnt really noticable - just dont want it affecting anything else

bryanb

Had a few done in MIL house a couple of years ago. The company removed the glass unit leaving the frame. They fitted new units. Cost about £25 for a window 2 ft square.
They lost on the job though as their measurements were wrong, so they had to make the unit twice for one window.

phill99

I've usewd a local 'Window Doctor' and they seem prety good. They don't fix the panes (at least I don't think they do) -they replace them. An average 600 x 1000mm should cost £50 - 70. The condensation inside means that the DG isn't working so letting your heat out!

ukwoody

Most glazing companies will also replace them. They measure them and get them made up. Cost isn't generally too bad. I dont think I've had a bill over about £70 for a unit.
Woody

travis-powers

As woody said most glaziers supply and fit, I believe you get condensation because seal has failed mainly because of poor fitting for a ball park figure for the glass
http://www.christieglass.com/pricecalculator.php
but I must say my local glass works is a little more expensive

McAzrael

travis-powers wrote: »

As woody said most glaziers supply and fit, I believe you get condensation because seal has failed mainly because of poor fitting for a ball park figure for the glass
http://www.christieglass.com/pricecalculator.php
but I must say my local glass works is a little more expensive

The units break down because they are not fitted correctly, but they also often break down because of plain old bad luck. Funny things, DG units.

sashman

Sealed units dont often break down because of bad luck!

Cheaper double glazing companies cut back on the sealant used, or dont drain the frames allowing the sealed units to stand in water means a good unit will last 5years tops.

what happens is the water exposes a weakness, breaks the seal, then moisture gets into the sealed unit. silic gel crystals do their best to absorb this new moisture but more gets in and the crystals evenually give up, thats when you see water in the unit.

well drained and ventilated they'll last for years (our office sealed units are well over 20 years old)

You dont have to replace the windows just the sealed units, generally £25 per metre in the trade, or £60 from a glazier/window doctor.

Always worth seeing if the guarantee is current and the business still trading

good luck

sashman

Mutton_Geoff

The condensation inside means that the DG isn't working so letting your heat out!

I don't think that's really true. The sealed units are only sealed, they aren't a vacuum or special gas. The condensation inside just means water has got in through expansion/contraction. It can't evaporate out so there is still an air gap between inner and outer panes, so the insulation effect will not have changed.

It's unsightly though, and I'm about to change mine, prices around £100 each for four large panes over 1200mm square. Check whether the window company is still in business and they are covered by a warranty. Also NHBC cover them for 10 years if your house was built after, I think, 1998/99. Prior to that double glazing wasn't covered.

ukwoody

Mutton, Phill99 is correct on both accounts. When a sealed unit breaks down it in effect becomes single glazing. This can create as much as a 70% drop in thermal efficiency (still better then single though). Many of the bigger companies make hermetically sealed units in a moisture free environemnet such as argon or helium when making the units. Some of the better units are also coated in a rubber compound around the edges to help prevent the breakdown of the edge seals. These often carry a 15 -0 20 year warrenty - but expect to pay more!

You will often find that over time, when units breakdown, you get a dark mark inside the units. This is due to a particulr mould that thrives on the stale air and condensation (i forget it's name now, years since I studied it).

Woody