Browse Forums Heating, Cooling & Insulation 1 Apr 16, 2016 3:07 pm Hi, i am new to the world of homebuilding, and i was just wondering how wide walls wound need to be optimaly for Maximum Thermal Insulation and Accoustic Insulation(or is it called Soundproofing) Re: Insulation(yeah plain topic, i know) 2Apr 16, 2016 4:31 pm The wider the better, but there are diminishing returns. In terms of thermal performance R2.5 inside a 90mm wall frame is as high as you can go in standard framed construction, and you should at least do this much. So with brick veneer, you typically have 10mm plasterboard, 90mm of frame with insulation, permeable membrane without outward facing reflective surface, 40mm cavity, 110mm of brick, for a total of 250mm. This is drawn as 240mm on plans, as they don't include the plasterboard. Once you go beyond around R2.5 in insulation, your windows are probably a bigger issue than your walls, and there are many issues to consider. The R2.5 HD batts to provide some sound isolation, and are a good basic inclusion for internal walls. Going up from there you can put in rockwool insulation for a little improvement. Other techniques include thicker plasterboard, like 15mm instead of 10mm, and doubling up the thickness of plasterboard. For theatre and sound studio type applications you can also mechanically isolate the two sides of the wall, with double framing, Re: Insulation(yeah plain topic, i know) 3Apr 18, 2016 11:07 pm The key question is location. There is a general assumption that more insulation is better, this assumption is held by a lot of people (including those who should probably know better, like architects, building designers and amazingly even trained energy assessors. This is not necessarily the case. In cooler climates, yes. In moderately warm climates, too much insulation can actually reduce energy performance because a heavily insulated building contains the heat built up during the day and does not cool down passively in the evening. Building Services Engineer Renovating our 1960's modernist home in Brisbane https://forum.homeone.com.au/viewtopic.php?f=53&t=82091 Re: Insulation(yeah plain topic, i know) 4Apr 19, 2016 9:17 am Optimal building design depends quite a bit on usage patterns. If you can open your windows overnight, then that will typically defeat the insulation when it's working against you, as long as there isn't too much thermal mass inside. But if you need to close the windows there's no way to do nighttime flushing, and then all that insulation and double glazing can easily keep a building hot even after it has reached a desirable temperature outside. Re: Insulation(yeah plain topic, i know) 5Apr 19, 2016 9:26 am Yes you're quite right, usage is basically left out of the debate as far as the BCA is concerned. It basically assumes that the building will be air conditioned or heated most of the time, in which case high R values for insulation and low U values for glazing is extremely important to ensuring those active cooling and heating systems operate efficiently - BUT in most areas of Australia it is possible to design a house that does not require active cooling and heating for the vast majority of the year - which in my view is the way we should be steering the industry. Problem is, to design a good passive house (especially in warmer climates) you need a decent sized block of land, with access to plenty of sun in winter, and room for wide eaves to keep the sun off of the walls in summer, and to allow lots of natural cross-ventilation. I don't see land developers changing their ways any time soon - 300-400m2 blocks are now the norm, so houses cannot really be well-designed - full stop. Building Services Engineer Renovating our 1960's modernist home in Brisbane https://forum.homeone.com.au/viewtopic.php?f=53&t=82091 Re: Insulation(yeah plain topic, i know) 6Apr 21, 2016 11:00 am Not a plain topic There is a big range of insulation to suit your needs, whether you are looking at thermal or acoustic properties. The number one thing to make sure when installing insulation is minimal gaps, you want to reduce air transfer as much as possible. There for accurate sizing for your stud distances and wall thickness is a must. Another thing to consider if doing a renovation, what about the existing home - does that have insulation? Happy to have a chat if you need. 1 5202 I had an old shower unit that broke on me and when I took it off, there were only 2 water pipes, instead of the normal 2 water pipes and a shower head pipe. S o I… 0 37538 The most definitive answer to your question James is this taken from the James Hardie Axon Cladding Installation Guide - i just happen to have it… 5 4307 |