Browse Forums Heating, Cooling & Insulation 1 Nov 11, 2005 11:24 am Hi
I am never ceased to be amazed at the amount of glass that is used in showcase modern residential building. Recent award winning homes seem to have whole glass walls....to take in the million dollar views admittedly...but how comfortable are they to live in? Architectural magazines are full of floor to ceiling rooms ...even bathrooms if privacy is available. Heating in winter would be an enormous cost.....I can't see these sorts of houses employing "close fitting drapes" to retain the heat in the house at night. How do they do it without incurring huge expense? Does thicker glass make that much difference that it can remain uncovered at night so that there is not such inefficient heat loss? Any thoughts? Geoff Re: All that glass 2Feb 15, 2006 10:41 am I think its not so much a case of thicker glass but of specially designed glass. Glass can be produced now that has special UV and sunlight filters, reducing heat transfer (kinda like tinting, but not so extreme, ie the windows arent black)
You can of course also get double or (if you are extreme) triple glazing. The blog of my home being built: http://glint-bladesong.blogspot.com/ Re: All that glass 3Nov 04, 2008 10:55 pm Glint-Bladesong I think its not so much a case of thicker glass but of specially designed glass. Glass can be produced now that has special UV and sunlight filters, reducing heat transfer (kinda like tinting, but not so extreme, ie the windows arent black) You can of course also get double or (if you are extreme) triple glazing. Yes, there are lots of options but you need to know when and where to use them. IGUs or insulated glazing units e.g. double/triple glazing - air or argon filled prevent convective heat loss. Most useful to prevent heat loss during winter or climates/orientations with poor solar gain. Tinted windows / low SGHC / low solar gain heat co-efficient - reduce infra-red radiant heat transmission. Most useful to prevent heat entry from intense solar radiation e.g. west/east facing windows. Low e glass / Spectrally selective / Spectrally coated = allow short wave infra-red solar radiation inward but reduces transmission of long wave infra-red radiation out. Useful again for winter applications particularly on aspects with good solar gain. You can combine features e.g. double glaze window with low e, double glaze with low SGHC Read this: http://forums.envirotalk.com.au/Overvie ... t7677.html Re: All that glass 4Nov 04, 2008 10:58 pm sarabah Hi I am never ceased to be amazed at the amount of glass that is used in showcase modern residential building. Recent award winning homes seem to have whole glass walls....to take in the million dollar views admittedly...but how comfortable are they to live in? Architectural magazines are full of floor to ceiling rooms ...even bathrooms if privacy is available. Heating in winter would be an enormous cost.....I can't see these sorts of houses employing "close fitting drapes" to retain the heat in the house at night. How do they do it without incurring huge expense? Does thicker glass make that much difference that it can remain uncovered at night so that there is not such inefficient heat loss? Any thoughts? Geoff Thick glass makes little difference to convective heat transfer. Only the air gap in double glazing can do this. If you can afford to put all that glass and steel in you can afford to spend $5000 a year on heating bills. The triumphs of a free market economy. Re: All that glass 5Nov 12, 2008 10:48 pm Yes you know we (wishful thinking) looked at a house like that from Rural Building Co, it had pretty much a wall of glass all along one side, but pretty much were told "oh we haven't built that design in the SW WA for years and if we have then windows were taken out". So even though all these really nice homes are used in the advertising still, in particular climate zones due to the compliance ratings they have to meet these days you will find that it's not that easy to build without taking extra measures (low e glass, double glazing etc).
For our current build we were going to have to have "comfort glass" and, or reduced window sizes, but they decided we weren't in the colder climate zone (it probably was borderline) so we got away without the extra $10k expense for comfort glass, and chose to have more tall skinny windows which reduced the glazing area a bit but still maximised the views. Honestly that really peeved me off - finding out we had to reduce the window sizes, and a fair few of them too, I mean that's one of the main things that attracts you to a house design isn't it? Anyhow we got around it, and I'm happy now, but maybe not so much when it comes time to clean them all!! But yes in the houses with expansive glazing I've always assumed it's different type of glass - I mean it would have to meet a certain safety standard first before you even think about the environmental factors. Re: All that glass 6Nov 13, 2008 10:11 am My two cents worth;
There is a little bit more to this topic than just the glass. House aspect is a major factor, yes some of these wonderful architecturally designed houses are full of glass, You might find they face the correct direction to warrent using all this glass, not just to capitolise on the views. Some of these houses intentionally leave as much sun as possible into the house in the morning to heat up the house, to increase passive solar gain in the house interior for the rest of the day. You might find that these glass walls (when they are in the wrong aspect)are covered overhead either with a major roof overhang, or shading device to cut out the sun when not required, reducing solar gain. You'll find is mandatory now for all dwellings to be compliant with Part J of the BCA, a major component of this Part J is filling out a Glazing calculator which determines if your house really does have too much glass in relation to the floor area. Lastly the BCA glazing calculator does not recognize 'drapes' as a solar control device. Hope this helps a bit, Pat. Re: All that glass 7Nov 13, 2008 2:21 pm Pat the draftie My two cents worth; There is a little bit more to this topic than just the glass. House aspect is a major factor You might find they face the correct direction to warrent using all this glass, not just to capitolise on the views. Some of these houses intentionally leave as much sun as possible into the house in the morning to heat up the house, to increase passive solar gain in the house interior for the rest of the day. Pat is right. I am only referring to glazing that is indiscriminate of aspect. Most people install glazing for aesthetic purposes or views rather than a method of controlling solar gain. Design with correct orientation, shading and combining with thermal mass can ensure that glazing provides energy efficiency rather than being an energy liability. A question. Im in Queensland and building a new home. We managed to reach practical completion 6 weeks ago but we haven't heard any date for handover yet. Who should we… 0 3053 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 15112 |