Browse Forums Building A New House Re: Why are wooden houses so popular in Australia? 21Jul 09, 2007 11:24 am A question probably for ausdesign,
Is it possible to put down foundations that will mean there is no cracking for double brick houses? Is appears that the culprit is clay so if the foundations go below the clay (and preferably to a shale or sandstone substrate) is it possible to have a house that is not prone to cracking? Perhaps bearing piers rather than friction piers are required (yes, I’ve been doing my reading). Double brick sounds so good from a thermal, maintenance and durability point of view, but cracking needs to be addressed. Is this possible? stonecutter, Am I reading this correctly, your parent’s new house used no brick in its construction? Cheers, Casa Re: Why are wooden houses so popular in Australia? 22Jul 09, 2007 12:12 pm Casa2 stonecutter, Am I reading this correctly, your parent’s new house used no brick in its construction? I think they used bricks to make a small retaining wall - but other than that - no bricks. It's a steep site sloping down from the street to the edge of the Georges River. It's 4 levels - concrete slab for each level 1. garage, 2. then a few steps down to entry, home office, art studio, bathroom 3. kitchen, main bedroom, laundry, living room 4. 2nd bedroom, 2nd living room & entertaining area The external walls are all some space age foam stuff - the covered the entire house in 2 days. Then rendered over the top of it all. The guy who designed the house desperately wants them to give the big home mags (like Vogue Living) permission to come in and do a story - but my dad doesn't want everyone seeing their stuff! Re: Why are wooden houses so popular in Australia? 23Jul 09, 2007 12:29 pm stonecutter,
Must be wonderful (for your parents) to have a house that qualifies for entry into a housing magazine. I see the house better now. Firstly, concrete slab on each level will help with the thermal mass. Also the outside is rendered is a consideration. Still eager to find out if it's possible to build a double brick house in Sydney that won't crack - then I'll have everything. Cheers, Casa Re: Why are wooden houses so popular in Australia? 24Jul 09, 2007 1:26 pm ausdesign Hey Casa - well put. I'd agree that the thermal mass on the internal walls is definitely an advantage but have a problem wih the inner skin of external walls taking the heat out to the cavity. Have you looked into this & how to insulate the skin ? In another thread, yak_Chat posted this link: http://www.greenhouse.gov.au/yourhome/t ... /fs16a.htm Just over half way down the linked page, I noticed this: "Reverse Brick Veneer (RBV) is much more thermally efficient because the thermal mass is on the inside, however good insulation is still important." That sounds to me a bit like what you are referring to here? Re: Why are wooden houses so popular in Australia? 25Jul 09, 2007 3:15 pm Interesting discussion folks.
Thermal mass is good - so long as it can be heated or cooled via the seasons - ie shaded via eaves / wide verandahs etc as needed with the seasons. Having owned a solid sandstone house in the Adelaide Hils which was in places 18 to 24 inches solid sandstone the thermal mass was nice. Once warmed by the 24x7 fire it stayed warm for days. What about tilt slab - I am surprised that everyone doing this ie townhouses etc are then lining it with timber and gyprock inside (maybe for sound or thermal) Why not houses? I was planning to build tilt slab house for thermal and costs. My design ideas are for tilt slabs south, east, west and maybe south - might line that end only - and then let the sun in the north land on a large thermal mass floor - with eaves - and shade the west with verandahs trees for summer. But I also like the look of timercrete -see link below. http://www.timbercrete.com.au/Timbercrete_Products.html The key is to thermally let it get hot when you want and not hot in summer. ie reverse brick as I've just read in another post is good as is the idea of the foam covered house - but you have to have areas to get the sun in where and when you want it. I think we have a long way to go before the sheep change direction - but it will happen. Baaaa Steve Re: Why are wooden houses so popular in Australia? 28Jul 09, 2007 8:10 pm Yak_Chat,
I like your idea of using tilt slabs. Seen very much in commercial buildings, but not much in residential buildings. (Tilt slabs are large concrete slabs that are then erected.) I was initially going to comment about the lower R value of concrete versus brick, but much to my surprise, brick has a thermal conductivity of 1.31 W/m.K, while concrete has a thermal conductivity of 0.29 W/m.K. That is, for the same thickness concrete has an R value 4.5 times greater (better) than brick. There is another good reason to use tilt slab with concrete floor slabs. I had lunch with a civil engineer friend of mine today and showed him my proposed house plans. Apart from saying that my design was aesthetically f***** and like something an engineer would design (I'm an electrical engineer ), he confirmed that bricks are prone to cracking. I asked whether the foundation could be done such as to avoid this. Apparently with time brick wants to expand and concrete wants to shrink. I wish I knew that a lot earlier. So I'm still worried about cracking in my proposed full brick house. Ahhhhhh, there's always another problem in the way. Cheers, Casa P.S. I will get an architect to improve some aspects of my design, but intent to keep the main floor plan. I like it! Re: Why are wooden houses so popular in Australia? 29Jul 10, 2007 3:39 am Casa2 I was initially going to comment about the lower R value of concrete versus brick, but much to my surprise, brick has a thermal conductivity of 1.31 W/m.K, while concrete has a thermal conductivity of 0.29 W/m.K. That is, for the same thickness concrete has an R value 4.5 times greater (better) than brick.! This is interresting, because I read somewhere that concrete is 5 times worse as brick in terms of heat accumulation. But even if not, too much concrete is not very good for the health, then rather wood. Re: Why are wooden houses so popular in Australia? 30Jul 10, 2007 3:42 am Casa2 he confirmed that bricks are prone to cracking. I asked whether the foundation could be done such as to avoid this. Apparently with time brick wants to expand and concrete wants to shrink. I wish I knew that a lot earlier. I demolished a 80 years old house and the brick wasn't cracked. And back then the materials sucked, the bricks produced now has to be much much better. Re: Why are wooden houses so popular in Australia? 31Jul 10, 2007 8:40 am Maybe we have more extremes in weather - drought vs floods, temperatures etc that are causing timber to shrink & expand more rapidly therefore causing more cracking?
There are some aspects of design that will always cause cracks: * brickwork connected to gyprocking - as Casa mentioned. We have this in our kitchen where above the rangehood is gyprock but the main part of the wall is brick - always cracking there * split level slabs - e.g. when you walk into our unit there is a small landing then 4 steps down to the living room. Every unit in our apartment either has steps up or down from the front door into the living areas. To do this - they had 2 separate slabs joined by the steps. In every single apartment, the section of wall near the join cracks terribly - about 7mm. The builder even admitted that they didn't know that it would cause problems & that they never build like that after they learned their lesson! Re: Why are wooden houses so popular in Australia? 32Jul 10, 2007 9:35 am stonecutter1309 I can see how it's easier to go double brick in places like WA where the soil is so stable. I thought Perth was predominantly a big sandpit. Not stable at all. Re: Why are wooden houses so popular in Australia? 33Jul 10, 2007 10:08 am Bud - my thinking is that it doesn't expand and contract the way clay does in other parts of the country - I could be very wrong! Re: Why are wooden houses so popular in Australia? 34Jul 10, 2007 11:29 am stonecutter1309 Maybe we have more extremes in weather - drought vs floods, temperatures etc that are causing timber to shrink & expand more rapidly therefore causing more cracking? That is very possible, of course. Old Home Restoration / Renovation To reduce noise transfer without compromising the aesthetic of your exposed I beams, consider filling the 100mm gap between the I beams and the floor above with dense,… 6 6785 If you don't want to annoy the neighbours then simply get yourself some good head phones. For me the sound is much better using headphones. The NCC (National Construction… 1 19004 Adam Baines Grad Cert Bldg Surv / Grad Dip Bldg Surv / MSAAPA Accredited Building Professional APB20210035 Builders Lic 183023 Pest Control Lic 84868 Ph 0412202336 PO… 3 33418 |