Browse Forums General Discussion Re: Double Brick Wall Cavity Insulation - Builder Wrong Prod 2Apr 21, 2023 9:11 am Architectural Homes & Duplexes - specialising in custom designing homes to your budget Get a Free Onsite Consultation Today or send a PM for information, questions or advice. Re: Double Brick Wall Cavity Insulation - Builder Wrong Prod 5Apr 23, 2023 12:22 pm Architectural Homes & Duplexes - specialising in custom designing homes to your budget Get a Free Onsite Consultation Today or send a PM for information, questions or advice. Re: Double Brick Wall Cavity Insulation - Builder Wrong Prod 11Apr 30, 2023 11:56 pm I am saying that double brick has similar thermal performance (or may be just slightly worse) due to thermal mass effect. It will be still very interesting to see the state of your framing after 10-15 years, considering the above mentioned construction. May be it will be fine, but I am still worried that even small doses of trapped vapour might eventually cause issues in the longer term. Rotten frames is something they dealt a lot with at the UK where they have used to put in a OSB board (also very low vapour permeability) in front of mineral wool insulation and even though they generally use vapour barrier on the internal side of the wall it was oftentimes damaged/punctured. BTW I hope that your wall sarking is vapour permeable though. As for NatHEARS, 6 stars is everyone getting these days, now 7 stars will be mandatory from September. But frankly, I wouldn't generally trust NatHERS calculations as they usually take 'perfect' conditions into consideration, e.g. not considering moisture inside the walls, thermal bridging etc. Thanks for the detailed comments chippy, I'll use this as a guide. 3 1637 As there is no sarking, there is a good chance that blow in insulation will be getting wet from time to time due to the rain water blown from the outside esp. during windy… 3 1219 Hi Kristy Around $1.7-1.8m or around $4,600/sqm. if you PM me your email I will send you a break up in a spreadsheet so you can get an understanding of the costs for… 1 13930 ![]() |