Thread: Low e glass V glass + film

Originally Posted by doug1

I am in the process of specing the glass for an extension with a glass area of 6 and 10 Sq M , facing East and North respectivly in Sydney

Does anyone have any input as to whether pilkington comfort glass or plain glass, (laminated or toughened is a better solution, and how best to compare the films to put on it?

Have a look here
http://www.greenhouse.gov.au/yourhom...ical/index.htm

heh, doug - best of luck with it, my comfort plus windows arrive on monday- when testing them, and standing in the sunlight - there was a pretty obvious difference between it and std glass - and like you I have an easterly (actually SE) window that summer makes the room as hot as hell by 9am, and cold as heaven (????) in winter.

The films can only effect heat gain not heat ingress/egress like the low emissivity glass. So cool in summer can be done with film but not cool summer, warm winter. Further, the film's necessarily are visible and effect the colour of the view outside, whereas you can now get totally clear comfortplus (and the other manufacturers also) - which for means the house windows look the same for both stories, given I'm not going to invest $5k on cp upstairs for the kids.

Cost - the cost to the window company is about $56 per square metre between 6.38 laminated and 6.38 CP - they'll probably tell you its $100/m - but thats their profit.

All I know is that when I was quoted for some windows recently and I asked about some of these fancy low-e glass products the bloke said to me that he could assemble double glazed aluminium windows for cheaper than a single glazed window filled with low-e glass. And that's with a Pilkington outlet just around the corner.....

There is different types of low-e glass & different configurations of double glazing.
I.e double glazing can have 4mm glass/ 6mm air / 4mm glass
3mm/8mm/3mm
3mm/8mm/3mm low-e

etc, etc

& then you can go to argon in the space etc
The window & glazing needs to be correctly designed for the climate zone, the application & the direction to get the best performance [in relation to cost]

No question....but show me a window supplier/manufacturer who gives a toss about that!!! So far they only seem to care about whether it is their product that fills the hole in the wall....

Which might go to show why we jumped at a house set of six twin double hung windows.....cost us nothing but diesel.

Originally Posted by SilentButDeadly

No question....but show me a window supplier/manufacturer who gives a toss about that!!!

Heres one: http://www.paarhammer.com.au/energy%20savings.html

If you have been to europe, the first thing you notice about the doors and windows is that our Aussie versions are underspec. I mean, what's the point of worrying about heat transmission and radiation through the glass when much of the actual real life heat ingress/egress occurs through leaky frames and almost complete lack of effective sealing when the window/door is shut?

woodbe.

If they don't give a 'toss' they won't be in business long.
Now that there is a 'window energy rating scheme' in place manuf. who aren't up with the game will find it hard to compete.
But point taken . . .if energy efficiency hadn't become fashionable they'd possibly be still selling glass to fill a hole.

Originally Posted by woodbe

Heres one: http://www.paarhammer.com.au/energy%20savings.html

Perhaps I should have said a 'typical' window supplier. Paarhammer are anything but typical in the Australian idiom.

Unfortunately they aren't local to me.....yes I know they deliver but the concept of embedded energy and the number of local window suppliers tends to make them an unrealistic option.

Like most stuff of any type available in the market these days........there's plenty of product but not much good design.

Advance
Affinity
Aneeta
Bradnams
Breezway
Canterbury
Dowell
Everglaze
G James
Rylock
Stegbar
Trend
Wideline

to my knowledge all are part of a nation wide rating scheme for energy efficient windows

Originally Posted by SilentButDeadly

the concept of embedded energy and the number of local window suppliers tends to make them an unrealistic option.

I hear you, but I have no idea how you are making those calculations.

Ok, the transport energy is an add-on, and probably the more efficient window takes more energy in it's construction by virtue of the nature of it's components. but if the concept of embedded energy is to be any use, doesn't it have to be balanced against the energy efficiency of the finished item over it's life? There should be a break-even at some point, and if that falls within the practical life of the window...

Because of the wild-card future energy costs, the financial calculations (dollar cost of window, compared to dollar energy savings x life of window) are hard enough, but isn't any window very difficult or even impossible to quantify on embedded energy terms?

woodbe.