Browse Forums Windows & Doors Re: Double glazing - VERY important? 4Apr 20, 2010 9:05 pm glockenspiel Hi, I was wondering whether it is really necessary to have double glazed windows? I presume you are doing this to improve the energy efficiency of the house and reduce heat loss. Here are the main sites of heat loss: viewtopic.php?p=278870#p278870 and their relative contributions. The most cost effective interventions to reduce heat loss in order are: 1. Good weatherization 2. Ceiling insulation 3. Wall insulation 4. Double glazing The first three easily pay for itself off in savings within 10 years. The cost advantage of DG will largely depend on your climate, the type of heating system you use and the cost of running that heat source. see viewtopic.php?p=280294#p280294 Note that heavy curtains with pelmets provide more insulating value than the extra glazing. If you cleverly orientate your living spaces to capture the north sun, you will greatly reduce your heating requirements. We have a passive solar design in a cool temperate climate and have not required daytime heating for the last 8 months. Direct sunlight keeps the living areas warm. This month our indoor temperatures fluctuate between 18-23 degrees for the daily cycle (despite average outdoor minimums of 11 degrees) with no active heating. Relative costs of DG are shown in the below link. Note that there are other reasons for cost variance in windows. Frame construction and material and the type of hardware used can have a significant impact. viewtopic.php?p=288135#p288135 Do you have a plan of your house and which direction it faces. What levels of insulation are you planning to use. Re: Double glazing - VERY important? 6Apr 21, 2010 11:56 am The windows are the first things we've upgraded. I arrived in Australia about 7 years ago, and I found the windows on Aussie houses of such a bad quality, I just couldn't believe it... I reckon that every new house should be built with double glazed on every window as standard. I'm really not used to be freezing in winter in my own house..and spending a lot of money in electricity heating this same house, and also heating the street ...the heat going out through that non isolated window!!!!! In France, you have now the option to get triple glazed windows (type on google: triple vitrage)...Double galzed is considered as standard, and nobody would build a new house with single glazed windows, that's just how it is over there... This so unusual here in Australia, that my window supplier made all my windows single glazed (I requested double)...they had to make them all again!! And still....I found 2 on the house not double glazed ..they have to come back again this week before the bricks go up..What the ??::wornout:: ?? I think a smaller house, better insulation, good orientation, double glazing...and you get a comfortable house all year around, with a low electricity bill (with solar panels...you might even get paid for the electricity you produce and don't use!..specially in the Aussie sun!)... I wish I was able to pick the supplier of my windows though ... I would have gotten a better price I'm sure...but well...that's how it is! Re: Double glazing - VERY important? 8Apr 21, 2010 2:20 pm Double glazing works well also to keep your house cool in summer...lots of energy saved on the long run! So I'd say Coffs Harbour, Melbourne, Tassie, Perth or Sydney..go for double glazed! And what i like with double glazed is ... the noise gets blocked from the outside... ...and I don't work for Ed!!! ... I just think that Australians miss out on something quite important for the quality of a home. Re: Double glazing - VERY important? 9Apr 21, 2010 6:16 pm There are so many factors that contribute to energy efficiency and a lot of them are cost neutral. A well designed house with single glazing could out perform a poorly designed house with double glazing. Different building elements have different functions. DG prevents conductive heat loss whereas the main reason a house overheats in summer is due to inadequate radiant protection. Check out the BOM webisite for the wide range of climates in Australia. You need to build for climate. Australia is not Europe. Re: Double glazing - VERY important? 10Apr 21, 2010 6:28 pm dymonite69 There are so many factors that contribute to energy efficiency and a lot of them are cost neutral. A well designed house with single glazing could out perform a poorly designed house with double glazing. True, but a well designed house with double glazing will outperform a well designed house with single glazing. dymonite69 There are so many factors that contribute to energy efficiency and a lot of them are cost neutral. A well designed house with single glazing could out perform a poorly designed house with double glazing. DG prevents conductive heat loss whereas the main reason a house overheats in summer is due to inadequate radiant protection. True... but double glazing using Low-E glass also overcomes radiant heat gain. In summary... the same house, well designed or otherwise will be more energy efficient with double glazing, but I would advocate good design up to the point where it permits a comfortable lifestyle coupled with good aesthetic appeal. Then correct the remaining inefficiencies with double glazing, and incorporate Low-E where the windows face the sun. Ed "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Double glazing - VERY important? 11Apr 21, 2010 6:42 pm I think PD use A&L & Dowell, neither of which do a sliding double glazed window. The sliding window is the cheapest of window designs and really doesn't suit energy efficiency as it leaks air. It will cost you treble to get it done in future, as you will pay for these windows, then pay again for double glazed and the removal of the old windows and installation of the new. Moving from sliding to awning could add 30%-50% and double glazing could add another 30%. Guessing your windows cost around $4,000, you are looking at a hike of $2,500 in cost plus the builder's margin, say $3,200 total. But it all depends on your area of windows, and how much the supplier charges. Replace all your windows later? Say $15,000 - $20,000 in today's money. Ed[/quote] Ed, I have Dowell sliding windows with double glazing. Re: Double glazing - VERY important? 12Apr 21, 2010 7:30 pm Bottom line is for most temperate climates it will help. Your mileage may vary. If you have the money the marginal cost is worth it because doing it later will cost a heap. If you are near the limit of finances you may still get away with a perfectly comfortable and efficient house without it (assuming you have done all the other right things) Re: Double glazing - VERY important? 13Apr 21, 2010 7:44 pm Dylan I think PD use A&L & Dowell, neither of which do a sliding double glazed window. The sliding window is the cheapest of window designs and really doesn't suit energy efficiency as it leaks air. It will cost you treble to get it done in future, as you will pay for these windows, then pay again for double glazed and the removal of the old windows and installation of the new. Moving from sliding to awning could add 30%-50% and double glazing could add another 30%. Guessing your windows cost around $4,000, you are looking at a hike of $2,500 in cost plus the builder's margin, say $3,200 total. But it all depends on your area of windows, and how much the supplier charges. Replace all your windows later? Say $15,000 - $20,000 in today's money. Ed Ed, I have Dowell sliding windows with double glazing.[/quote] No worries, I got it wrong. But A&L don't have dg sliding. "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Double glazing - VERY important? 15Apr 22, 2010 3:08 pm Our builder uses A&L as well and we wanted DG. They make them in a Casement Window. That means they have a winder like the awning but they wind out sideways and open like a small door. Great for catching a breeze and directling it back into the house. SK Build thread: viewtopic.php?f=31&t=34120 Handover 23 Dec 11 Squatting 21 Dec 11 Fixed 12 Oct 11 Plastered 31 Aug 2011 Framed 7 June 2011 Site Start 7 Feb 2011 Land Titled 18 Jan 2010 Land Deposit 25 Jun 2009 Re: Double glazing - VERY important? 16Apr 22, 2010 5:47 pm Thanks for all the input guys! Very helpful! Keep them coming Re: Double glazing - VERY important? 17Apr 23, 2010 8:14 am Problem is that building companies take advantage of those who want things like double glazing and they inflate the costs. Cut the windows out of your contract and find them yourself. If they don't like it show them the door. Don't let the building company dictate you what you can and what you can not. You are the boss. You call the shots Change is what we need! Can we? YES WE CAN!!!!! Re: Double glazing - VERY important? 18Apr 23, 2010 8:57 am We are building with Hermitage Homes and for our 41sq home the cost to go to double glaze windows to the whole house was $4,000. My brother is building with Simmons and for a 21sq house the cost quoted was $10,000! Just shows the difference in cost from builder to builder. Our house thread: https://forum.homeone.com.au/viewtopic.php?f=31&t=18335 Re: Double glazing - VERY important? 19Apr 23, 2010 11:57 am windowexpert Problem is that building companies take advantage of those who want things like double glazing and they inflate the costs. Cut the windows out of your contract and find them yourself. If they don't like it show them the door. Don't let the building company dictate you what you can and what you can not. You are the boss. You call the shots Unfortunately - and I mean that - the larger builders can do better prices on the base home because they have contracts in place, and these contracts may preclude alternative suppliers from supplying. So if you want their home, that's the rule. But there is also another rule that the builder can add only 25% margin to extras. So even if you do want another supplier it should not be so punitive. Ed "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Double glazing - VERY important? 20Apr 23, 2010 12:35 pm Fred I arrived in Australia about 7 years ago I did 20+ years ago... unfortunately agree with you... but have not seen much change... Perhaps the energy is still too cheap. dymonite69 Note that heavy curtains with pelmets provide more insulating value than the extra glazing. Will not stop moisture condensation in my experience. I do not understand how can a family live with considerable moisture condensation (foggy and wet glass, water dripping down the window structure, on to the walls) on the inside of the windows in cooler months in Melbourne caused directly by single glazing. That's reminiscent of living in a caravan van. Have you ever noticed how much mould http://en.wikipedia.org/wiki/Mould growth on the windows? I wonder how this contributes to health (e.g. asthma) of the inhabitants who breathe the spores in, or as in case of children, they pick the mould from window glass and frames and either eat it rub the spores in to their skin and eyes. For example, I have never seen mould inside of homes in several European countries (richer and poorer), or Japan, but see it every year again and again in Melbourne in our current (single glazed) house, friends houses and in my previous houses. Agrhhh... read this story http://forum.homeone.com.au/viewtopic.php?f=1&t=23220&hilit=mould Anyway... there are many other considerations that might be more or less important re DG for anyone of us. On the new house, we are considering all windows DG as a must. Built a 2 storey house... hebel, proctor, pvc windows, aiphone, deck roofs, louver covered patio This is one of the reasons I decided to go overseas for my double glazed windows. As the builder indicated, he's worked on many upmarket builds, these were the most well… 13 19245 The worst thing you can do is sign a building contract without a pre contract review. Over the years many people have come to me with disputes where they just signed… 0 8339 Hi - thanks for your reply. Yes I think 'Ill go for whitish with very speckly bits rather than pure white something like this. PS was actually 2008 I built the… 2 11696 |