Single Glazing vs Double Glazing

[Flyboy]

Hi all,
We're trying to get approval to build a house at the moment, and one of the things the council has come back to us with is we might be required to have double glazed windows to meet the BASIX certificate.

Does anyone know a rough price (per sqm) for single and double glazed windows?

cheers

[Trav]

I don't know the price, but I've heard that it is basically double the cost of single glazed windows (ie you don't get much of a economy of scale with double glazing).

Trav

[jackiew]

got quotes for this about a year ago ... I do know that it wasn't double the cost of single glazing. It can be worth getting quotes from a firm who specialise in double glazing - in my ( albeit limited ) experience some joinery companies don't want to be bothered with it and consequently seem to want to charge you a p**s off price.

In the end I didn't go for it because the windows were a temporary solution to the howling gale coming through the louvres in a bodgy existing extension. If I'd been aiming to keep the extension in the long run I would have definately gone for double glazing.

[Woodlice]

Definitely go to a place that specialises. Nothing worse than having unsealed double glazing from a company that saved you $50 at the start only to find mould and algae surviving on the condensation in between your glass. As fun as it may sound, if you want a fish tank for a window, get one that is easier to clean.

J!

[silentC]

You have got to be kidding!! They want you to have double-glazing in Sydney? I would be looking at other alternatives to improve the rating. Put in a rainwater tank or something. There's no way you need double glazing in Sydney, it's just ridiculous. Sounds like another fiasco. The local council probably hasn't got a clue on how to handle this new BASIX stuff. I asked our local building inspector about it and he couldn't even tell me what it was called.

[Flyboy]

Thanks for the replies everyone. Yep, the whole BASIX thing is an absolute sh*tfight. I've already got the rainwater tank and solar hot water (with a gun held to my head), but unfortunately you need to comply in each seperate category (stormwater, water, energy effeciency etc) individually. And you are dead right when you say that no one knows what's going on. Council don't have a clue, and the BASIX website has no phone no. and the email goes to a dead link.

Could go on for hours, but back to the windows. Another alternative BASIX offers is something called pyrolytic low-e glass. Only problem is none of the glazers know what that is (at least the 3 that I called). One has a product called ComfortPlus glass (about $75 extra per sqm) which they think complies. All the energy coeffecients are in fact better than double glazing, so you would think it would be OK. But I guess if common sense came into it I probably wouldn't have needed to start this post.

Said it was unfortunate I wasn't a day earlier as one of the BASIX assessors was in the shop doing research on the different products. I'll probably know more than him when I'm finished with this.

Cheers

[silentC]

Try this one: 1300 650 908. Found it buried on one of the pages. Bet you the person you talk to there has no idea either :rolleyes:

We're about to go through the process of getting approval for a new house. Fortunately, BASIX doesn't come in down our way until July this year, which gives me 4 months to get the application in and through. Reckon I can do it? Bloody hope so. :(

[Grunt]

You could try the double glazing method they did on one of the windows in my place. Instead of having a gap between the panes they are pressed together.

It's really good. None of the advantages of double glazing and all of the disadvantages.

I can barely see through them now. I need to take all the panes out and clean them. Yet another job on the list.

[simon c]

Another alternative BASIX offers is something called pyrolytic low-e glass. Only problem is none of the glazers know what that is (at least the 3 that I called). One has a product called ComfortPlus glass (about $75 extra per sqm) which they think complies. All the energy coeffecients are in fact better than double glazing, so you would think it would be OK.
ComfortPlus is made by Pilkingtons - it is a compliant low-e glass. There is lots of info on their website here:
http://www.pilkington.com.au/channels/Pilkington/Australasia/Australia/English/building+products/products/energy+management/products/pilkington+comfortplus/benefits.htm

[silentC]

I had a bit of a look around on the BASIX site. A bit scant on details but nowhere do they mention double glazing. Their 'compliant' house has awnings or eves over all the windows though to assist in shading. My place will have verandahs all round because I'm a good Aussie boy.

Found this quote:

"Window manufacturers report that BASIX is already significantly raising homeowners´ and builders´ awareness of the very real importance of building energy efficient dwellings."

Ian Frame
Executive Director
Australian Window Australian Inc.

(Ian Frame - How's that for nominative determinism?) I'll bet the window manufacturers think it's a brilliant idea. :rolleyes:

[simon c]

The energy compliant process doesn't dictate anything, it works on points. If you choose not to have double-glazing, you just make up the points in other ways. Eaves and orientation are probably the best ideas.

[silentC]

The energy compliant process doesn't dictate anything, it works on points.
I suppose that was my point. I've heard a couple of mentions of councils requiring double glazing etc but from what I can see, they can't use BASIX to insist on it. It just seems like an easy answer for them to say "hang the expense, get double glazing". I just think it is ludicrous to suggest it in a place like Sydney. Sweden maybe, but Sydney?

[Flyboy]

I cheated and gave BASIX a call (thankyou silentC). After a bit of a group huddle amongst themselves they decided that ComfortPlus was a "pyrolytic low-e" glass, so I guess that's what I'll have to use.

The glazing section is on the BASIX site under Thermal Comfort. You'll probably have to register. I've tried every combination of eaves/shading with all the different types of glass, but there is no way it will pass without double glazing or ComfortPlus. What we are doing isn't excessive either. 50sqm of glass for a 240 sqm house. The eastern and western walls are around 150 sqm with only 6 sqm of glass.

You can make up points in some parts of the certificate. For example, I had to have an indoor clothes drying line to avoid having fluoro lights throughout the house (don't ask because I don't know). Unfortunately, the glazing section is completely seperate from the others and it has to be passed in its own right. It doesn't matter how many rainwater tanks you have, too much glass, no building approval.

What's really annoying is we were considering not having airconditioning. But you actually end up with more points with airconditioning than without. So now we're being forced to install aircon in an attempt to save energy. Try and figure that one out.

[silentC]

Sigh...

I'll just repeat my earlier comment: looks like another fiasco.

Oh well, I just hope like hell I can get our place approved before it comes in down our way...

[bitingmidge]

Fiasco is right.

Our last three houses have been desiged (carefully) to take account of climate, (ecohouses in modern jingoistic talk) and all were extremely successful, warm in winter and cool in summer.

I had them checked out by a friend who was in the process of becoming a certified assessor, and they all barely made a couple of stars. (Despite the fact that we have no need for air conditioning, ceiling fans or heating!)
:confused: :confused: :confused:

Turns out the software in use (by legislation) was set up to Victorian standards with no account of the different climatic conditions here. Heaven help the blokes in Townsville.

To make matters worse, the guys driving it (by and large-there are SOME clever certifiers) have no understanding of how to make a house work with climate. In one situation I was forced by the certifier to provide a one metre wide awning to a ground floor window facing west, despite the fact that it was four metres from a two storey building in the same complex, and therefore in complete shade from about 2.pm in summer, and never caught winter sun!!!

Aaaaaaarrrrghhhh..... these are the same people that throw rocks at coppers .... I'm sure of that!!!

Death to the Blithering idiots!!

P
:D

[silentC]

Yes, looks like those blithering idiots are at it again.

It will be very interesting to see what does happen down our way when it comes in. If they start forcing people to put in air conditioners, it will probably lead to open revolt. Currently, our average temperature at midday is 26 degrees. What am I going to do with an air conditioner?

I read somewhere that they had created climactic zones and that these were supposed to be an input to the process. It would be totally ludicrous to assess a house in Darwin on the same criteria you would use in Melbourne. Having said that, I can easily believe that this is exactly what they are doing. :rolleyes:

[simon c]

Fiasco is right.

Our last three houses have been desiged (carefully) to take account of climate, (ecohouses in modern jingoistic talk) and all were extremely successful, warm in winter and cool in summer.

I had them checked out by a friend who was in the process of becoming a certified assessor, and they all barely made a couple of stars. (Despite the fact that we have no need for air conditioning, ceiling fans or heating!)
:confused: :confused: :confused:

Turns out the software in use (by legislation) was set up to Victorian standards with no account of the different climatic conditions here. Heaven help the blokes in Townsville.

To make matters worse, the guys driving it (by and large-there are SOME clever certifiers) have no understanding of how to make a house work with climate. In one situation I was forced by the certifier to provide a one metre wide awning to a ground floor window facing west, despite the fact that it was four metres from a two storey building in the same complex, and therefore in complete shade from about 2.pm in summer, and never caught winter sun!!!

Aaaaaaarrrrghhhh..... these are the same people that throw rocks at coppers .... I'm sure of that!!!

Death to the Blithering idiots!!

P
:D

I agree it is a fiasco, but some of the problems you are quoting appear to be problems with interpretation by the assessors. The software uses the climate zone you are in, so if you are in a different zone then it will adjust to that. Also, there is a comment about if your property is significantly overshadowed by a building, then the software calcs don't apply and you have demonstrate a different way.

PS I'm fundamentally in agreement with this process - so many new houses going up in Victoria over the last few years have been terribly designed - large windows to living agreas that face the sun all day and have no eaves so the aircon just pumps out. However, if they don't get this right - then a good idea will suffer through bad implementation.

[journeyman Mick]

..........Death to the Blithering idiots!!

P
:D

I was going to weigh in with something here, but it looks like MIdge beat me to it! :D Quoting me, from memory :cool: .

Mick

[ChrisH]

I think you will find double glazing is MUCH cheaper than that low-E glass. I compared about a year ago and the low e glass was astronomical yet didn't perform as well as double glazing.

I made my own windows with double glazing - I'm in the otways in south west Vic, so it actually makes sense here. I made the timber frames and bought double glazing inserts made by MOEN glass in Bayswater, an outer suburb of Melbourne. Their prices are amazingly low, they were a pleasure to deal with and delivered the units to me out in the sticks for about $300. They deal all over the country so Sydney should be no problem. I couldn't recommend them higher.
During installation I broke one unit - naturally it was the biggest one. As only one pane was broken I carefully removed the broken glass, cleaned up the frame, phoned a local glass joint for a price for a single sheet of glass so I could repair the broken unit - $96.
I phoned Moens for the cost of a complete new double glazed insert - $63. Go figure.

The energy rating systems (I'm not familiar with basix) consider frame material as well as glazing - are you proposing aluminium frames? They always rate worse than plastic or timber, as aluminium conducts heat very effectively so defeats the use of insulation elsewhere.
The current Owner Builder magazine has an excellent article on the serious problems with these energy rating softwares, how they come up with nonsensical results.

Chris