Double Glazing - PVCU v WOOD?

emma_b_4

we had wooden sash windows for 4yrs, they were 100yrs old and looked good on the inside but the outsides needed painting quite often and looked scruffy quite quickly. we had them replaced with double glazing last decemeber and got the wooden looking windows, they are light brown (honey oak? they might call them) and look more or less the same

George_Bray

RedOnRed wrote:

An installer told me and not the one that fitted our windows, so he was in fact completely independent.

And was he scientifically qualified/educated to say? We're all a product of what we read, and our general level of education, I guess. By that, I mean I haven't done any original research/tests into this issue. But the basic physics of thermal conductivity give me reason for hope. I'm surprised the U figures on the web page you pointed to are only 1.5 for K/argon like mine, compared to 1.7 for K/air. That's still a greater difference than your initial "0.01%" and miles better than 2.7 for ordinary double glazing with air.

I mentioned a vacuum. We all know that a vacuum flask keeps water hot for hours. The thermal resistance of argon, suggests it should be about 40% along that track of thermal resistance, compared to air. Who knows if the windowstoday U figures are very accurate?

Regards
George

RedOnRed

George_Bray wrote:

And was he scientifically qualified/educated to say? We're all a product of what we read, and our general level of education, I guess. By that, I mean I haven't done any original research/tests into this issue.

Like me, I don't think he would have the time, facilities or inclination to do research or a full lab analysis on this matter. He's just an ex installer who happens to think, as I do too, that the argon additive makes little to no difference.

You will see lots of adverts from double glazing companies boldly stating that there is argon in their sealed unit cavities, but none of them will actually state what the U value difference is. That's because adverts normally make bold claims like 10% - 75% off or something, so a 0.3% saving hardly hammers home.

Yes, we are all a product of what we read. That's pretty much how I learnt to read and know all I know.

George_Bray

Here is one 'article' about the use of Argon, to significantly reduce heat loss. Surely, every high quality window installation, e.g. by an environmentally concious company for their property, will use Argon. All the serious written material suggests it is worth doing. I hope others haven't been put off.

START OF QUOTE:
What is the advantage, and expected life, of purchasing gas-filled double-pane windows?
The advantage of having argon gas between the panes of glass is that argon transfers less heat than air does. Argon has a lower U-value because it is denser than air. This reduces heat transfer within the air space.
Argon-filled glass windows have U-values ranging from 0.40 to 0.31, while air-filled windows have U-values of about 0.5. For homes with a significant amount of window area, about 25 to 40 percent of the house's square footage, this U-value difference can cut energy costs significantly.
Over time, argon gas may leak out of the space between the panes of glass. The amount lost depends on how well the window was manufactured and the quality of materials used. Argon leaks are usually caused by failure of the seals between the glass and the edge spacer. Also, some gas is lost because it diffuses through the seals. Even if the argon gas does leak, the window's thermal performance isn't affected much as long as there is no noticeable failure of the seal. Tests have shown that if an argon-filled window leaks five percent of its gas each year, it will lose only 12 percent of its R-value after 20 years.
END OF QUOTE

Argon is also widely used by divers in their dry suits because they know it keeps them much warmer than air.

Source: http://www.engext.ksu.edu/henergy/envelope/windoors.asp

chuckles1066

Leftynick wrote:

Hi,

We 're in the process of buying a house which has dark wooden double glazed windows. They dont look that old (maybe 5 years?) but my partner thinks we should get them replaced with PVCU before we move in as because they're wood they'll rot etc..

Thanks

Wood + Damp Britain = Rot

Staining or treating wooden frames only hardens the outer layers of the wood, the insides will slowly rot away because the damp moisture penetrates wooden fibres........when my wife and I bought this place, the kitchen window only was double glazed and had been treated *every* year (I know this because my father in law owned the house prior to us and had the window installed).

When we came around to replacing all the windows in the house, the installer was able to rip the framework of the wooden window out with his bare hands.

External wood and Britain's climate are a no-go!!!

RedOnRed

George_Bray wrote:

Here is one 'article' about the use of Argon, to significantly reduce heat loss. Surely, every high quality window installation, e.g. by an environmentally concious company for their property, will use Argon. All the serious written material suggests it is worth doing. I hope others haven't been put off.

There's nothing wrong with argon. In fact it's better to have it then not to have it and no one is trying to put anyone off it.

If you consider a difference of 0.1% - 0.19% to be a significant difference then that's open to debate...that's all.

The point is, should you choose to grasp it or not, not having argon doesn't mean that you're throwing a significant amount of money away. We've both proven the margin is negligible.

The thing that is important to note is that if you have some wide boy double glazing salesman visiting you who is trying to flog his product at an inflated rate because his has argon and a competitor doesn't - you may now know better.

RedOnRed

chuckles1066 wrote:

Wood + Damp Britain = Rot
External wood and Britain's climate are a no-go!!!

Did you have softwood windows - which would explain it?

Regularly maintained hardwood windows will last forever if treated properly and softwood will last for years with the right treatment too. In Scandinavia they use a lot of pine for their windows and have harsher weather then ours.

Next time you walk past a really old building like a church or something you might be able to see the door is wood and probably hasn't been treated for decades, but beacuse it's most likely hardwood it's fairly naturally resistant to the elements.

chuckles1066

RedOnRed wrote:

In Scandinavia they use a lot of pine for their windows and have harsher weather then ours

Harsher as in colder - yes for sure.

The key word in my post was damp!! We have one of the moistest(sp?) climates in the world - I did see it explained once by a meteorologist, something to do with Britain's latitude and longitude on the planet coupled with cloud formations and gulf streams but it all went over my head

I'm up at 5a.m every morning and even in the middle of summer the grass is saturated with dew.

You may well be right about hardwood/softwood differences but to me wood and Britain's climate don't go together

FirstClassMale

Originally Posted by RedOnRed
In Scandinavia they use a lot of pine for their windows and have harsher weather then ours

I have just bought a log cabin made of softwood. The difference is that it is from Finland where the trees grow slower and makes the timber stronger. As has been said further back in this discussion, it is our perception that pvcU is indestructable that boosts the salesmen of windows profits. One way to get rid of window companies who phone me is to say "They will be in wood wont they?" and the phrase they hate me using is "plastic windows".

Luckily, the house we have just bought has wooden window frames and the french doors we intend to install will be in wood too.

often one of the trouble with having pvcU window frames fitted is that the installer just takes out the old frames they leave the wooden supports inside some window cavities and fix their plastic to this wood. Expansion foam is then squirted into any gaps which means the insides of the cavities cannot breathe and in extreme cases the foam will expand to the point where it pushes the new frame out of alignment.

eilz

DO uPVC windows come in any other colors apart from :

White,
Honey (wood effect) and very Dark Oak(i think effect its oak).

I am looking for something in-between Honey and Dark oak, but nobody seems to do them?