Browse Forums Heating, Cooling & Insulation 1 Jun 09, 2009 10:21 pm Our architect recommended R1.5 for the walls and R3 for the ceiling. Because we are getting a steel frame that is 76mm wide we are kind of limited as to how thick we can go... I am now trying to work out how much insulation is going to cost us but am finding it very difficult to get any quotes. So I thought I'd look at some of the websites which list the insulation prices. Now the only problem is, what type of insulation do I need? Fibreglass, polyester, or rockwool? I am thinking we can put the foil insulation on the outside walls (between the steel frame and bricks) as it isn't very thick. But what about the rest? I guess we need thermal insulation on the outside and ceiling and sound on the inside walls? Is this correct? Any help would be greatly appreciated Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 2Jun 10, 2009 2:16 am I'd suggest you want / should install higher R levels than that. Recommendation for Adeladie is r1.9 and R3.2 respectively and better than that by another few % is normally acknowledged as being cost effective. ie R2/2.2 and R3.5/R4 for the Adelaide Plains, a bit higher for the hills. http://www.yourhome.gov.au/technical/fs47.html#levels Give me an idea of your budget and I can do some suggestions for you. Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 3Jun 10, 2009 10:58 am Yak_Chat I'd suggest you want / should install higher R levels than that. Recommendation for Adeladie is r1.9 and R3.2 respectively and better than that by another few % is normally acknowledged as being cost effective. ie R2/2.2 and R3.5/R4 for the Adelaide Plains, a bit higher for the hills. http://www.yourhome.gov.au/technical/fs47.html#levels Give me an idea of your budget and I can do some suggestions for you. Thanks for that. We don't really have a set budget, but we don't want to spend overly tooo much. If that makes sense. Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 5Jun 10, 2009 11:55 am borg If you are doing the install on by yourself go Poly. If you just going to contract out the work get fibreglass. Am for R2 for walls and R3.5 for ceiling. I find fibreglass really irritates my skin and respiratory tract. You need masks. The limiting factor in some installations is the thickness of the cavity especially in the wall or a say in a cathedral ceiling. We couldn't get more than R2 into our 90mm wall cavity. Squashing thicker stuff in defeats the purpose because it is the air pockets that create the insulating effect. Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 6Jun 10, 2009 12:08 pm dymonite69 borg If you are doing the install on by yourself go Poly. If you just going to contract out the work get fibreglass. Am for R2 for walls and R3.5 for ceiling. I find fibreglass really irritates my skin and respiratory tract. You need masks. The limiting factor in some installations is the thickness of the cavity especially in the wall or a say in a cathedral ceiling. We couldn't get more than R2 into our 90mm wall cavity. Squashing thicker stuff in defeats the purpose because it is the air pockets that create the insulating effect. This is what scares me. Because our steel frame is 76mm wide which I guess means that the wall cavity will be 76mm? Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 7Jun 10, 2009 12:13 pm gettingThere dymonite69 borg If you are doing the install on by yourself go Poly. If you just going to contract out the work get fibreglass. Am for R2 for walls and R3.5 for ceiling. I find fibreglass really irritates my skin and respiratory tract. You need masks. The limiting factor in some installations is the thickness of the cavity especially in the wall or a say in a cathedral ceiling. We couldn't get more than R2 into our 90mm wall cavity. Squashing thicker stuff in defeats the purpose because it is the air pockets that create the insulating effect. This is what scares me. Because our steel frame is 76mm wide which I guess means that the wall cavity will be 76mm? Probably. (and unfortunately steel is also a great conductor and will reduce the net insulation value of the building envelope via thermal bridging). Check out the pink batts website for datasheets on thickness and R value. I recall that in the course of my research that polystyrene boards have slightly better insulation per unit thickness but they are more expensive. They also have the advantage of not degrading/compressing over time. You may wish to explore that option. Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 8Jun 10, 2009 1:47 pm dymonite69 gettingThere dymonite69 I find fibreglass really irritates my skin and respiratory tract. You need masks. The limiting factor in some installations is the thickness of the cavity especially in the wall or a say in a cathedral ceiling. We couldn't get more than R2 into our 90mm wall cavity. Squashing thicker stuff in defeats the purpose because it is the air pockets that create the insulating effect. This is what scares me. Because our steel frame is 76mm wide which I guess means that the wall cavity will be 76mm? Probably. (and unfortunately steel is also a great conductor and will reduce the net insulation value of the building envelope via thermal bridging). Check out the pink batts website for datasheets on thickness and R value. I recall that in the course of my research that polystyrene boards have slightly better insulation per unit thickness but they are more expensive. They also have the advantage of not degrading/compressing over time. You may wish to explore that option. Is this the sort of thing you are referring to? http://www.lunavalk.com.au/product_list ... e&Variable[ProductCodeID]=POLYBSR50 http://www.lunavalk.com.au/product_list ... e&Variable[ProductCodeID]=POLYR2060 Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 9Jun 10, 2009 5:14 pm Quote: So I thought I'd look at some of the websites which list the insulation prices. Have a look at http://buybuildingsupplies.com.au/information.php?info_id=31, it'd give you an idea of prices of batts. For polysterene try Isoboard, http://www.isoboard.com.au/index.html, they do 75mm thickness, but is't more expensive than batts. Chris My father rode a camel, I drive a car, my son flies in a jetliner, his son will ride a camel.Saudi saying Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 10Jun 10, 2009 9:00 pm I'd go foil on all outer walls and under the roof + soundscreen rockwool on the outside walls, fibreglass on the internal walls glass in the ceilings. That can easily give R2.0 on the outside walls R1.5 on internal walls R3.5 or R4 for the ceiling rockwool is not too bad to work with - glass - nasty stuff. Polyester - your doona is made of it Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 11Jun 10, 2009 9:35 pm Yak_Chat I'd go foil on all outer walls and under the roof + soundscreen rockwool on the outside walls, fibreglass on the internal walls glass in the ceilings. That can easily give R2.0 on the outside walls R1.5 on internal walls R3.5 or R4 for the ceiling rockwool is not too bad to work with - glass - nasty stuff. Polyester - your doona is made of it Thanks for that! Re: Fibreglass Vs Polyester Vs Rockwool Vs Foil Insulation 12Jun 14, 2009 4:10 pm Hello Gettingthere, My suggestion is polyester all over. R1.5's in poly for your walls will be around the 70-75mm thickness depending on the manufacturer. Also polyester is a great acoustic insulator as well, being that its generally a denser material. For your ceiling r3.5 poly would great, the tradespeople you will have in your roof in future, will thank you for being so kind to them(poly is easy to work with, without the whole ppe issue and because its generally in batt for is easy to move around if you ever need to locate tops of walls in your ceiling. Polyester is my personal favourite when it comes to insulation and is a mid priced insulator. Now for the other insulations. Rockwool is terrible to work with, feels and smells disgusting, I have handled a fair bit of it installing it and its not fun. It is on the other hand cost effective and does the job its made to do. Foil is great as a moisture barrier on your external walls. Generally the BCA rule is builders wrap is to be installed on external walls and as a system value comes out at around the 1.3 depending on what time of year. If you were thinking of foil batts in the external walls and ceiling my suggestion is stay clear. People often are getting them replaced because they are not doing the job they were made to do. Foil only works when it is clean and free of dust(Which you can find in large amounts in your roof). Foil needs to reflect the heat in order to work. And they are only ever sold in a system value.(taking into account the 'R' value of things like your gyprock and the air space and roofing material) and oftern times they collapse soon after installation. Also another option may be Earthwool. Its a little more expensive than fibreglass but not as expensive as polyester. It is a new insulation on the market made from recycled glass bottles and sand and bound together with an organic material known as "ECOSE technology" It does away with all the added formaldehyde, acrylics and phenol that ordinary fibreglass has in abundance. My suggestion is if you don't want to spend the extra coin on the polyester earthwool would be a great substitute. Anyway my suggestion is either Poly(my personal favourite. I'm going to be kitting out my reno and theatre room with all things polyester.)or Earthwool. check out www.higginsinsulation.com.au and call the guys in melbourne to get a price! Ron I am in the same situation, would you be able to give some insights in to this? I am in SA 8 12828 I am saying that double brick has similar thermal performance due to thermal mass effect. It will be still very interesting to see the state of your framing after 10-15… 10 23180 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 8929 |