Do i need new double glazing and how much to pay ?

[AndrewWDIYNOT]

I have 20-25 year old aluminium double glazing (and external doors)in a 1960's semi, the glass does not appear to be turning blue, however every winter I wake up to find the windows dripping with water, and the wall paper around the windows(first 2-3 inches) growing black mold. Is this stuff safe ? (even though the windows are wiped every morning). The old brush seals have been replaced with a modern seal, to stop all the noise and wind coming in between the windows

Apart from the additional security offered by new upvc windows , child opening restriction & built in air flow. Will changing from my current windows to new UPVC ones help . I have noticed how cold the (frames and) glass feels in the morning, could this mean the gas between the glass as gone and they are not working properly

 

[stem]

Aluminium frames are colder than wood & PVCU, so do provide a cold surface for condensation to form on. The space between the panes of glass in older units often is also smaller so does not provide so much insulation.

My parents replaced some single glazed draughty metal windows contained in wooden frames in the mid 1970's and found whilst the draughts dissapeared, condensation started forming that hadn't in the past.

If the seals have failed allowing air to get between the panes, there will normally be condensation / misting on the inside of the glass.

Newer windows are less prone to condensation than older aluminium types because they have better thermal properties. However, if you generate a lot of humidity for example by cooking or drying clothes indoors without proper ventilation, or insufficient heating, you will still get condensation albeit a little less.

As for cost, you get what you pay for generally.

 

[JohnD]

you have a condensation problem not a window problem. Does anyone drape wet washing about the house?

//www.diynot.com/wiki/building:condensation_in_houses

New double glazing windows are so expensive that they have negative payback (i.e. if you kept your money in the bank for the life of the windows, the interest would be more than the cost of energy saved)

However if you have got to fit new windows for some other reason (rotted, rusty, building a new house) then you may as well fit good ones.

BTW plastic windows (and especially doors) are very weak and insecure, that's why they are festooned with hooks and bolts to try to make up for it. You can still cut through them with a good-quality breadknife, though.

 

[freddiemercurystwin]

JohnD, do you have an obsession with condensation?

 

[JohnD]

I have an obsession with people who are so stupid that they drape bucketfuls of water around their homes, soaked into wet clothes, and then complain that their homes contain water.

 

[keveljay]

Aluminium windows offer very little, or no thermal break compared to modern multi-chambered uPVC units. The outside temperate is transmitted directly through the frames, like heating one end of a metal rod - the other end will eventually get hot, and as the ambient temperature at this time of year is significantly lower than the inside temp, condensation (sweating) forms readily. There is no solution other than replace to combat this. I think JohnD has painted an overly-bleak description of modern uPVC windows and doors as most modern 70mm casements are reinforced with steel box-section, and door panels have an MDF core to prevent people with 'bread knives' burrowing through them Try to get quotes from smaller independant suppliers that friends etc can recommend - basic economics should tell you that they don't have the same overheads (big premises, accountants, sales people etc) than the nationals do, so it won't sit heavily on the bottom line of your bill. Always specify a top 'fit-and-forget' profile like Rehau or Kommerling and get 3 quotes - play them off against each other and watch the price tumble - its a buyers market

 

[crank39]

Sound bit of advice there from Keveljay although JohnD isn't a million miles away with what he says also!

 

[sunroom4u]

a good upvc branded window with trickle vents a 24mm or 28mm Double glazed unit and a multichambered frame (maybe with the new thermal inserts) will definately reduce heat loss through the window and reduce condensation - it will look better too

security is no problem - go with someone who has the security kitemark

cheers