Browse Forums Heating, Cooling & Insulation 1 May 06, 2009 1:24 pm Currently going through the building design brief. Builder has indicated insulation for internal ceilings to be R3.0 insulation batts. I am in WA and would like to ask if thats all the insulation i would require? pardon for my ignorance. Do i still need to get someone else to install extra insulation? thanks! Building in Harvest Lakes, Atwell (Perth) status: design phase with builder Re: R3.0 Insulation? 2May 06, 2009 1:49 pm Where abouts in WA are you? Have a look at this for more about insulation levels http://www.yourhome.gov.au/technical/fs47.html#levels Re: R3.0 Insulation? 3May 06, 2009 2:30 pm I am in perth. The site recommends R3.2 for Perth. Is it a big difference between R3.20 and R3.0? Question is, even if i upgrade to R3.2 for the ceilings as recommended on the site... does it means that i would not need to consider other forms of insulation? Thanks! Building in Harvest Lakes, Atwell (Perth) status: design phase with builder Re: R3.0 Insulation? 5May 06, 2009 6:06 pm Hi Championboxer, We're currently building in the SW (Nannup area) and have R3.5 insulation in the roof. I think they originally were talking about "comfort glass' and cavity insulation but we had been zoned wrong so that was taken out. We are building a double brick house though and still had to comply with a certain window to brick ratio to prevent us having to pay a lot of extra $$ for stuff like comfort glass (if we wanted really big windows). One reason why Rural Building Co can't really build some of the more flash looking designs in the SW like the Rivergum Skillion any more. I have heard a lot of people say that it's a good idea to pay extra and get the "sisal, or sarking" or whatever the silver stuff that goes under the roof is called. I'm currently living in a shed that has just the roof lined with the stuff, and it does make a big difference. I would have put it in ours but we couldn't really afford it, besides I figured that it's only the roof space and should be ok as long as the insulation does it's job. Only problem is that it isn't something you can just go and do later - well I guess you could but it would be a lot of work and wouldn't end up being as efficient as if it was installed first up. If you're not building a brick house I would certainly make sure wall insulation is included. Re: R3.0 Insulation? 6May 07, 2009 1:41 am Pebble I have heard a lot of people say that it's a good idea to pay extra and get the "sisal, or sarking" or whatever the silver stuff that goes under the roof is called. I'm currently living in a shed that has just the roof lined with the stuff, and it does make a big difference. I would have put it in ours but we couldn't really afford it, besides I figured that it's only the roof space and should be ok as long as the insulation does it's job. Foil blocks >99% of radiant heat. With batts the surface gets heated to high temperatures (higher than the air temperature) by the heat radiating from under the roof. The R values also become temperature dependent and are reduced by the summer heat (probably something to do with enhanced convective air movement within the batts). Re: R3.0 Insulation? 7May 15, 2009 10:54 am CB, assume you have a tile or metal pitched roof? Dynomite is right you should definitely have sarking / sisaltion under the tiles. Make sure the they install it right ie must have an airspace, so it goes sarking, then battens, then tiles. Go for the max R you can afford on the batts, but beyond 3.5 doesn't make that much difference. Assume you are double brick? Assume you are insulating the cavity with foildboard or wall wrap. If not you should definitely do this as it will make a big difference. Is it slab on ground? Re: R3.0 Insulation? 8May 15, 2009 2:37 pm Insulation for ceiling is important as it the most exposed area of a house. Nonetheless it is important to have a relatively equal insulation throughout the house. It's a bit like having a roast in the oven but leaving the door open if you don't get it right.
The rating software system is not 100% accurate with that. You can get away with concentrating on one aspect. If you are after living comfort you should look beyond the figures that you get from rating and a general recommendation. The recommendation are sometimes existing since the 90s - meaning they are not up to date and don't reflect the possibilities of modern architecture and building. In regard to the glazing I would recommend to look at something better than just clear glass. With up to 87% heat through windows and doors in a standard dwelling we are definitely talking about the weakest part in the building envelope. Looking at double glazing is not an extra cost; it's an investment in comfort. The earlier you consider these aspects like roof insulation and others, the lesser costs you will have in the long run. Especially with windows and wall insulation retro-fitting is a massive expense. Best regards
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 11441 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 6391 |