Browse Forums Heating, Cooling & Insulation Re: Comparison of insulation upgrades 14Oct 26, 2020 10:18 pm Thanks to everyone for your comments, it's helped pick up a few errors in my original calculations (now fixed hopefully) and made our decision much clearer. We'll just upgrade the windows to low-e. The ROI isn't great at over 30 years, but it does save a fairly significant amount of energy and I believe it will have comfort benefits in a few locations where people may be seated near a window. The $ saved from not doing the other insulation upgrades will mean we can get the solar panels a little sooner. It will pay for about half of a 7kw solar which should generate an average 25kwh per day which is significantly more than the 2kwh or so saved by the insulation upgrades (the solar does have a shorter lifetime than the insulation though). Re: Comparison of insulation upgrades 15Oct 27, 2020 3:17 pm 24 sq house with flat metal roof with anticon insulation, maybe 25mm, mostly windows and some double brick, concrete slab heat to 22 if under 10 outside, heat from about lunch time to 10pm Re: Comparison of insulation upgrades 16Oct 27, 2020 5:00 pm just found this calculator https://www.builditsolar.com/References ... atLoss.htm Re: Comparison of insulation upgrades 17Oct 29, 2020 6:54 am They all look like very minimal upgrades. As you can see from the ROI, financially none of them are worth it. You haven't really said much about your double glazing. What type of frames are specified? If they are aluminium frames, then I'd be spending money upgrading these to uPVC (might be a similar price), timber or thermally broken frames. As aluminium has very high thermal conductivity, these frames become very cold in winter - leading to condensation, & possibly mould - & hot in summer. I'd be looking at low-e glass for any unshaded eastern & western windows are least. In saying that, with good design you should have very few western windows. But I'd be looking to do something that will save you a lot of money, & greatly reduce your hearing & cooling loads. Reducing the size of your home. 40SQ is more than 150% the size of the average Australian new build, already the largest homes in the world. Not only will reducing the size of the home save on building costs, heating & cooling costs, maintenance costs & shorten the time to clean the home. It will also be much better for the environment, greatly reducing the embodied energy in the home. Embodied energy is the energy (& emissions) that have gone into the build. All the energy used creating all the building products. The energy used to mine the raw materials in Australia. The energy used transporting these materials to China. The energy used converting these materials into the manufactured products. The energy transporting these materials to Australia, & to your building site. As you'd expect, the embodied energy in a home is very LARGE. On average, the embodied energy in a newly built home roughly equals about 15 years worth of operational energy! A large, energy efficient home, far more. So the GHG emissions created building your 40SQ home may equal all the energy you'll use in the home for 30 years! Not great for the environment. On top of this, large houses need large blocks. Leading to more urban sprawl. Creating longer commutes to work. Far, far worse, urban sprawl leads to elevated levels of land clearing. Australia has the highest levels of land clearing in the developed world. Even before the bushfires last year, the koala was a threatened species. Why, land clearing! It's be building smaller, & smarter. You'll save money, & be able to spend some of your funds on better design. Ditch any thought of gas in the build. Go all-electric. Install a good sized solar PV system on your roof. Hey guys building a new place through a volume builder and just wondering if i should complain to the site supervisor as we just had plasterboard installed. Looks like… 0 11269 1000000% definitely add insulation. I have in my home and it makes a big difference minimising sound transfer. Insulation is pretty cheap and definitely worth it 2 6191 |