Double Glazing Energy Savings

Cardew

I had a house built eighteen years ago. It has extensive glazing and, as was perceived wisdom in 1988, I specified sealed unit double glazing in hardwood frames. I got them from a firm that was reputed to be the best manufacturer and they cost serious money.

Now there are several schools of thought about the energy savings attributable to double glazing, but most authoritative sources indicate that 10% of heat is lost through single glazed windows and double glazing will certainly reduce that.

However! Last year I had to replace my first glazed unit - a standard window about 40”x18”. It had ‘blown’ and misted up inside. The cheapest quote I could get for replacement was £110. I hate to even think of the cost of the large French windows.

Now another window has blown and it would appear from the internet that 10-20 years is a normal life for these sealed units. If that is so I am going to be faced with some large bills for replacement over the next few years.

Given the ‘cowboys’ who operated( and still operate) in the double glazing market I wonder how long some of their units might last.

My point is that given the additional expense of fitting these units, and the ongoing expense of replacements, these costs certainly outweigh any savings on my heating bills. I would have been much better off with single glazing.

I do appreciate that for some people the reduction in noise is an important factor.

Has anyone else had experience of replacing sealed units, their life and their cost?

melbury

We have experienced exactly the same problem as you with double glazed units in wooden frames. We have lived here for 15 years and replaced loads of the windows - including one of the sliding patio doors - because they have "blown."

Some of the replacements have also blown again over the last couple of years and we have taken the decision to gradually replace them with a good quality thickness single glass!!

It just seems to be a problem caused by the wooden frames, but having said that there is nothing that would induce me to have the plastic frames (personal pet hate!) and I have heard about quite a few problems occurring with these.

Cardew

melbury wrote:

We have experienced exactly the same problem as you with double glazed units in wooden frames. We have lived here for 15 years and replaced loads of the windows - including one of the sliding patio doors - because they have "blown."

Some of the replacements have also blown again over the last couple of years and we have taken the decision to gradually replace them with a good quality thickness single glass!!

It just seems to be a problem caused by the wooden frames, but having said that there is nothing that would induce me to have the plastic frames (personal pet hate!) and I have heard about quite a few problems occurring with these.

Thanks. What is the difference in costs between your good quality single glazing and double glazing?

melbury

Well not a lot really because my husband gets the glass cut to size and fits them himself - I would say about £12-£15 each for a pane about 24" x 20".

melbury

Sorry didn't answer your question properly - I don't know how much it would cost to buy the double glazed glass, we have never enquired. Just got fed up with replacing it.

Ken68

Havn't read all on this site but recall him writing that single glazing in hardwood frame is the best.....http://www.askjeff.co.uk/content.php?id=1

Cardew

Ken68 wrote:

Havn't read all on this site but recall him writing that single glazing in hardwood frame is the best.....http://www.askjeff.co.uk/content.php?id=1

Thanks, interesting series of articles. The payback time of 100 years for replacement double glazing is a real eye opener.

I note that some manufacturers give a 10 year garantee for metal and 'Plastic' frames but only 5 years for timber frames.

When any more of my windows become 'blown' I will replace them with single glazing.

The lesson to be learnt seems to be that nobody should bother with having double glazing unless noise is a particular problem.

TEDDYRUKSPIN

Nice post. Probably everyone with wooden / timber frames with double glazing will experience this problem and especially windows facing the south.

A hundred pound quote seems expensive as the biggest one's I got replace cost 60 pounds and smallest 20 pounds. This included labour.

I really liked the tip that single glazing is much better. My parents house have single glazing with a wooden frame and have never had a problem. Their house is 25 years old and mine is 10 years and have resulted in misting.

So the lesson to be learn't is forget the double and get an extra thick single glass which will do the job. All this thing about insulation and noise cut out is a joke.

Now would you purchase the triple glazing? I would'nt.....

:money: