Public radio this AM had a BBC segment on green/environmentalists calling double glazing (or it’s use) “immoral”.
Well, I agree DG is stupid and a gross waste of money and resources, and salesmen for the stuff are just a step above used car sales, but “immoral”?
How many of you are in areas where the local building code literally REQUIRES insulated glass (aka double glazing in the UK)?
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Replies
Wasn't Howard Stern talking about that just the other day?
No..wait...that was the BBC again talking about how the new high-efficiency burners we have to use today waste more energy than they save because of increased maufacturing and maintenance demands.
Thank goodness for NPR and the BBC!
Al Mollitor, Sharon MA
Double Glazing, insulated glass, "immoral", don't really understand this. Maybe there is no need for insulated windows in the UK, but here in Michigan, USA, double insulated glass is the only way to go. Anytime to can save energy, both heating and cooling, has to be a good thing.
Double glazing is "immoral"?????
I guess the option is to burn more energy to keep warm, or eliminate windows altogether and burn more energy for lights? Or maybe anything other than living naked in a cave is "immoral"???
No wonder my ancestors left GB. Between that and Prince Charles deriding the education system for allowing people to believe they could rise above their station.
Harrumph.
I didn't hear the segment, but it seems top me a whole slew of information is necessary before reaching that point.
Where they talking about in new construction or of replacement windows?
What are the aggregate increased costs and use of resources in producing them?
What are the energy savings? What are "comfort" advantages? (Reduced draftiness, warmer surface temp so less radiated heat, etc.)
If I recall, there was a tidbit in FHB many years ago about a TVA study that showed that the payback time for a storm door when added to a well insulated and weatherstripped entry door is around 50 years.
So in some cases, adding storm doors might be considered as "immoral," at least in the sense that any "waste" is "immoral"
The key to forgiving others is to quit focusing on what they did to you, and start focusing on what God did for you. Max Lucado
Sojourners: Christians for Justice and Peace
The report was well below most BBC reports I've heard. It was slanted. The reporter made several remarks about how 'dreadful' the buildings looked with the 'new windows'. They only interviewed one contractor. One who did not like 'double glazing'. From what I could tell, it's like the "Tin Men" of 40 - 50 years ago here. there are guys going around 'solving' owner's window maintenance problems by replacing the old sash with cheap vinyl pocket windows.They commented that PVC 'fades and falls apart in a few years because of the uv light. We had the same problem till the early 90's when they came up with UV stablized materials that don't discolor. My guess is there are a lot of crappy windows being sold and installed; and now all double glazed windows are getting a bad rap in the UK because of it.I'll have to call my wife's (shes' a Brit)family to see what's going on sometime.MGMG
PVC is bad for the environment because a large amount of Chlorine is used in its manufacture, much of which is released into the air/water.PVC has poor durability in sunlight, compared to painted wood or anodized aluminum, because it is, by nature, a brittle, hard material. Plasticizers are added to PVC to give it flexibility, but the chemical bond is poor (compared to other plastics) and the plasticizers begin 'off-gassing' from the moment the material is produced, eventually leading to it becoming brittle and easily damaged. True, the chemistry has improved in the last 20 years, but it is still going to happen over time.A painted wood window can be maintained, for ever. And a wood window made with real old growth wood (like the old windows in an old house that survived the 80 years or whatever until now), that have been reasonably cared for can be still usefull for that much longer. But a PVC material that has been exposed that long eventually becomes junk, and can not be maintaned or repaired. Scrap PVC can not be recycled. It is just landfill.The auto industry is very much getting out of the business of using Vinyl/PVC because of all these reasons. Finding alternative materials is difficult, because also Urethanes are not recycleable, so TPOs and other types of materials are being developed to replace them. In autos, the PVC and Urethane are used for soft-touch surfaces to give a quality feel on a budget. The problem that housing has is that the window frames need to be quite stiff with just enough flex to avoid cracking and right now wood and aluminum seem to be about "it" and they cost more. Dillemma for anyone building new and looking to 'do the right thing' on a tight budget.My advice for anyone in an old house is, as already stated by others above: seal up the attic plane, insulate with air-impeding insulations and add exterior storms (which help protect the original windows as well).Norm "PVC sucks" Kerr
I also heard that BBC report. I agree with an ealier poster that it was biased, although they did quote someone from the window industry who pointed out the negative environmental impact of maintaining "timber" windows ... the manufacturing and repeated application of paint, for example.
The report suggested that the vinyl windows had a limited lifespan due not only to material failure, but also to changing styles and tastes. And all that discarded PVC ends up in landfills.
As a preservationist, I will hate to see the British law emulated here (it's illegal there to install single-glazed sash ... for window replacement or for new-builds). I'm currently replacing modern vinyl double-glazed windows with shop-built 9-over-6 wood sash, using recycled early-19th century cylinder-glass panes. There is no way I could replicate the orginal look with modern glazing.
And I'll admit the house is getting noticeably colder with each "new" old-style window.
For a modern house, I would use double-glazed wood windows ... which the BBC report mentioned as a tiny part of the market because they are difficult and expensive to manufacture. True?
Allen
Nothing particularly difficult about manufacturing double-glazed wood windows, compared to single-glazed. I think bedding with glazing compound isn't recommended, as it may cause problems with the seal, but there are various techniques for mechanical seals that will work. (Most manufactured wood sashes are simply assembled around the pane, with only a dash of glazing compound or some such for a weather seal.)Probably the biggest problem re wood is that the seals on modern double-glazed panes are fairly wide, so you need a pretty deep notch for the pane (to hide the seal), vs what you'd use for regular glass. This could compromise the sash strength somewhat, and will likely influence the sealing technique. And, of course, if you want some sort of divided lite look you have to compromise with glue-on grids or some such (though these can certainly be wood if you wish).
It's all relative man. If you don't like PVC, why bother going after windows- the real evil would be vinyl siding! MUCH larger volumes/weights of PVC are used in siding than in windows, and since it often looks like crap even when it's brand new, much less after years of sun exposure, lots more of IT ends up in landfills than do vinyl windowframes!
PVC's got a bad rap because it's been misapplied. It's a wonderful material of construction relative to many alternatives in common use. And it represents basically zero hazard in a landfill- it merely occupies space for 10,000+ years as it is totally inert when buried and protected from UV. Then again, in a proper landfill, conditions are DRY so you can dig up newspapers from over a hundred years ago too. A landfill is NOT a bioreactor and it is not intended to promote biodegradation- quite the opposite in fact. So people who think they're doing the environment a favour by choosing so-called biodegradable materials are doing basically nothing if these materials end up landfilled.
PVC may be considered a hazard if it is burned in an incinerator, but that's because we're stupid about incinerators. Burn it in a cement kiln and you get zero dioxin/furan formation- and you get calcium chloride in the cement, something which is added in cold climates already. That goes pretty much for all chlorinated organic wastes- burnt in cement kilns, they represent little disposal hazard. But unfortunately, technical sense isn't the dominant factor in making decisions about issues like this- it's fear and ignorance on the part of the general public which dominates our technological decision-making process in this area.
I'm not saying wood isn't a wonderful material to make windowframes out of- it is. Wood is a wonderful building material and I revere its beauty, it's renewable origin, and its ability to basically be a near-permanent storage medium for atmospheric carbon dioxide. But wood requires maintenance, unless it's clad with something. And most people have better things to do with their lives than to spend their spare time painting windowframes.
Junkhound,
You asked <<Who lives in an area that requires double glazing>>
Everyone who lives in Canada.
All new construction requires at least double glazing or equivelent.
You can get by with storm windows on renos in some jurisdictions (mine is British Columbia).
The gov't here uses the carrot and the stick. Mandatory use on new construction and no tax on double glazed units.
With windows (at the most basic level) being so inexpensive, I wouldn't consider using single glazing in even the most utilitarian garage. Someone eventually will want to turn it into a workshop or pottery shed or spare room or......
Alan
... or a show.
I see some problems with double-glazing, or the replacement window biz in general.
One is that multi-glazed windows would appear to have a very short lifespan before the seals blow. They also tend to be disposable, because not all are repairable, or pane replacement may be prohibitive.
Placing the focus on the glass itself is another problem. The perimeter seals are far more important than fancy triple low E glazing when it comes to net heat loss.
Another problem is that windows are not generally the 'weakest weatherization link'. Most structures have large convective leaks through the attic plane. The cold air may find its way in around a lower story window, but that is more of a symptom than the problem.
Spending tens of thousands on replacement windows has lousy payback compared to a couple of thousand to seal up the bulk air leaks that cause the real cost and comfort problems.
However, there is a whole lot more money to be made marketing fancy windows, and people can see and touch them. Let's face it. Weatherization work is not sexy. Hey, check out my new attic hatch! And those sealed pipe penetrations! That's 3 feet of cellulose, baby!
Well, it's definitely true that there are a lot of crappy window installs, especially when done by the quickie window replacement folks, and when the install is crappy, the utility of the double glazing is fairly well compromised.But that doesn't negate the merits of double glazing, especially in northern climes.Re the seals, decent quality windows will hold their seal for 20-30 years, with maybe a 5% failure rate over that period. Many manufacturers warranty the glazing for 10-20 years.
I have mixed emotions - I sit at the computer looking out a 90 yo double hung w/storm - I've refurbished the operable sash once and the storm twice in the past 28 years - gotta change the storm for screen seasonally, big window, heavy storm, at least it's an easy reach...
if I look another way, there is a bank of recycled thermo panes - (early ones, somehow the double pane were formed not with two sheets and a seal, but the edges are actually glass, manufactured in one step - a 1/4" hole near a corner and a plug - two of them have fogged...
I'm currently refurbishing some wooden sash for a blank wall in the kitchen - single glazed with a storm panel fixed directly to the sash - fixed picture window with operable casements on either side - got it figured out, except for the casement hardware/latches - winter fun in the shop...
"there's enough for everyone"
The recycled windows likely failed due to the handling during recycling. Every time I've seen a double-glazed window fail there's been some evidence of "trauma" to it.
If they could make glass with inherently better R value AND excellent clarity, they would have something. Single glazing does almost nothing to stop heat loss, double does a little better, but they block a lot of noise from the other side. Re: the PVC issue, they recycle that and regrind a lot of it. Unfortunately, it gives off Hydrogen Chloride when it gets over a certain temperature. "Doughnuts, is there nothing they can't do?"
"I cut this piece four times and it's still too short."
cs....
i started with single glazing and storm windows... 1973...
since 1976 it's been all insulated glass.. and in a manufactured window, i've never seen one fail ..
we've also sold and installed thousands of insualted fixed glazing panels, they may sometimes fail.... but usually if you are dealing with a known fabricator, and they are properly supported and installed,, they won't fail either..
a slanted install is more prone to failure than a vertical install.
we have a lot of site built windows with fixed insualted glass that are now going on 25 years with no fogging and no seal failure
i have seen a lot of single glazed windows fail in that same time..usually the putty and paint fails do to lack of maintenance..Mike Smith Rhode Island : Design / Build / Repair / Restore
Hey!!!!
Whats all this window crap??!!! I thought this was a thread on doughnuts!
Does anyone have a reference or web sit that gives numbers on the financial/economic cost to produce a single or double glaze ( window or doughnut) and the payback time/period.
m2akita
-being a doughnut
I heard that piece from the BBC on windows Wednesday. (It was fun listening to them talking about window frames made of "timber.") As I heard it, the thrust of the discussion was at PVC. The concern was that PVC was environmentally hazardous to produce, and it becomes brittle when exposed to UV light, so it will be burned or dumped more often than "timber", creating more pollution.
Hmmm...Wonder how long the vinyl cladding on Andersens will last....
Al Mollitor, Sharon MA
I heard the segment a few days ago. What I came away with was the problem/ concern was with PVC frames and not so much the glass necessarily. Although they did mention problems with fogging. Perhaps thier edge/seal technology is what we had in the 70's.
They also made the point that the new windows don't look good in the old buildings and don't have the look of the old wood sash they replaced. - That isn't an issue with the windows, that's an issue of what the building owner/architect/ contractor decided to use. We can get double glazed windows here that look nearly 'authentic.'
I think IGUs (insulated glass units - AKA 'double glazing) Kick butt! When you look at energy performance of single glazing compared to IGU (especially when you have low-e glass), it's remarkable. I live in a house with almost as much glass as wall area. I'm in a 9000 heating degree day climate. If I had single glazing - even with storms - I couldn't sit around my house without a down coat this time of year.
Glass needs vary by climate. In many parts of the country (sunbelt) you'd be waisting your $ on IGUs. In hot sunny climates you need reflective glass or good overhangs (traditional) to minimize heat gain.
Here, I must use (new code as of July 1) windows with U-factor of .35 or lower. That means IGU and low-e. I usually get gas filled for a couple extra bucks.
In GB, where the BBC report was from, - their winters aren't nearly as bad as the northern US and CAN. For them it probably doesn't make economical sense to use IGUs (they claimed the payback was 100 years in the report).
Now on the vinyl question - that's another whole thread and definately loaded with lots of opinions because of the environmental issues.
MG
This may be the article/issue: http://news.bbc.co.uk/1/hi/business/4035343.stm
Excerpts follow:
"The British government's efforts to cut energy use in homes has singled out windows for special attention. All new and replacement windows now have to be double glazed to cut heat loss. "
...
"Many environmentalists acknowledge that double glazing helps cut energy use, but they also argue that PVC is a damaging chemical. "
...
""The problem we've got in the UK is that we are sending about 10 million windows a year to landfill. Maybe half of those are coming from demolished buildings," Mr Kay says.
"The other half is coming from the window replacement industry and it seems as though the window replacement industry is trying to educate people to think that windows are a consumer durable, like a washing machine."
Keep in mind that Britain (and also Europe) are much more densely populated than the US and waste disposal is a VERY BIG DEAL there......
Egon
Basically the same problem as in the US: There is a huge "replacement window" industry that sells windows based on claims of lower heating costs, lower maintenance, etc. However, often the windows are so poorly constructed and installed that heating costs rise and the windows fall apart after a few years.The problem is the salesmen.
I can think of a lot of things more immoral (and more fun!) than insulated glass.