Browse Forums Building A New House 1 Dec 12, 2021 8:58 pm Hi all, I'm very early in a knockdown rebuild process with Masterton (i.e. at the tender process) and have a couple of questions regarding insulation. As a bit of background I'm going to have R4.0 ceiling insulation plus an R1.3 anticon blanket for the roof so I'm pretty happy with an R5.3 for the ceiling (house is located in the Hills District of Sydney). The standard insulation to the external walls is R2.5 but the cost to upgrade it to R2.7 is $3,500 which seems excessive to me. I'm just wanting to know if this is a worthwhile expense? i.e. will it make a significant difference in the thermal performance of the house? Please note that the exterior of the house will be wrapped with the Bradford 'Enviroseal 'wall wrap (not sure of the R rating of this wrap) and that all windows will be double glazed (hopefully with thermally broken aluminium frames - waiting on costings for this). So in short, is there that much difference in thermal performance between R2.5 and R2.7. Another question - I just found out that the internal walls will NOT be insulated. I'm having three rooms (guest bedroom, main bedroom and theatre room) insulated with acoustic insulation (special price of $900). But now I'm thinking, do I need to have the other internal walls insulated to improve thermal performance of the entire house? I'm thinking it is unnecessary as the downstairs is pretty open plan, and the cost to have all internal walls is an extra $3000. Again, I just don't feel like it is a wise allocation of limited funds. But happy to hear all your opinions and advice. Thanks in advance! Re: Insulation questions 2Dec 14, 2021 3:19 pm cstanis2000 Hi all, I'm very early in a knockdown rebuild process with Masterton (i.e. at the tender process) and have a couple of questions regarding insulation. As a bit of background I'm going to have R4.0 ceiling insulation plus an R1.3 anticon blanket for the roof so I'm pretty happy with an R5.3 for the ceiling (house is located in the Hills District of Sydney). The standard insulation to the external walls is R2.5 but the cost to upgrade it to R2.7 is $3,500 which seems excessive to me. I'm just wanting to know if this is a worthwhile expense? i.e. will it make a significant difference in the thermal performance of the house? Please note that the exterior of the house will be wrapped with the Bradford 'Enviroseal 'wall wrap (not sure of the R rating of this wrap) and that all windows will be double glazed (hopefully with thermally broken aluminium frames - waiting on costings for this). So in short, is there that much difference in thermal performance between R2.5 and R2.7. Another question - I just found out that the internal walls will NOT be insulated. I'm having three rooms (guest bedroom, main bedroom and theatre room) insulated with acoustic insulation (special price of $900). But now I'm thinking, do I need to have the other internal walls insulated to improve thermal performance of the entire house? I'm thinking it is unnecessary as the downstairs is pretty open plan, and the cost to have all internal walls is an extra $3000. Again, I just don't feel like it is a wise allocation of limited funds. But happy to hear all your opinions and advice. Thanks in advance! The conduction of heat is proportional to the temperature differential each side of the wall. Inside your home, I doubt that it would be worth the expense of the insulation. "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Insulation questions 3Dec 14, 2021 3:55 pm For internal walls, i'd go with acoustic insulation, rather than just thermal. But whether it's worth the dollars to you, is the question only you can answer. We're looking to do it in our new house, since it's one of the pain points in our current house, and we want to ensure that the whole house can't hear a toilet flushing or someone watching the tv in the living room. Re: Insulation questions 7Dec 15, 2021 1:13 pm cstanis2000 Thank you both, that is very helpful For internal walls, it's a bit more complicated. You have to take into account how you plan to use your home, while also understanding how the systems that heat and cool your home work. In my situation, I'm building a single story home in Melbourne. It will have ducted heating system that provides heat to the main living area and bedrooms, no zoning. It will also have an air-conditionar that can heat and cool the main living area. I ruled out evaporative cooling as it would negate my extra investment in double glazing. So I added insulation to the internal walls in the main living space and a door to shut off that area from the rest of the house. If I happen to be home during the day on weekends: In summer, if I need to, I can run the AC for just that area while keeping the door closed. In theory, the same can be done in winter to heat just that area during the day. No need to heat or cool the other rooms as they are not really being used during the day. This setup will make even more sense if I get solar panels installed. If I need to heat the house at night, I can then use the ducted heating system for the entire home as this is when I'm more likely to use the other rooms as well. For this system to work properly, I just need to make sure all the internal doors are open so that air can flow back to the return air duct. Because I'm working from home during the week quite often, I also had the internal walls of one of the bedrooms insulated. That room will be used as my home office. So instead of having to heat the entire house during the day, I can use a small space heater to heat just that single room. As it is south facing, I'm hoping it won't need extra cooling in summer. And for that week or two a year when it does get too hot, I can always move to the main living area that does have A/C. For me, the sound-proofing was just an extra benefit. Re: Insulation questions 8Dec 15, 2021 1:27 pm Thank you all for your advice. Patrik, completely agree with your logic about taking into account with how the house is going to be used. The downstairs kitchen, living and dining areas are all open plan so there aren't actually any internal walls to insulate! (the wall adjoining the garage will be insulated). So I will just go with my original plan of only insulating the three bedrooms that are used the most. Like you state, I will just have to take into account how many zones to have when it comes to air-conditioning so that I'm not heating or cooling areas that aren't occupied much. Re: Insulation questions 9Dec 15, 2021 1:32 pm cstanis2000 Thank you all for your advice. Patrik, completely agree with your logic about taking into account with how the house is going to be used. The downstairs kitchen, living and dining areas are all open plan so there aren't actually any internal walls to insulate! (the wall adjoining the garage will be insulated). So I will just go with my original plan of only insulating the three bedrooms that are used the most. Like you state, I will just have to take into account how many zones to have when it comes to air-conditioning so that I'm not heating or cooling areas that aren't occupied much. i'd consider insulating the ceiling space between floors as well. we currently live in a 2 story house with living area being open plan as well, and the noise travels quite a lot between floors. you can easily hear dogs running upstairs when watching tv downstairs, or the tv noise in the bedrooms when someone watches it downstairs another thing to keep in mind, that this will pretty much be your only opportunity to do it. unlike a lot of other things, it won't be practical to do it after construction is over, and it will be way way more expensive. Re: Insulation questions 10Dec 15, 2021 9:44 pm Hi Strannik, thanks for the tip and yep - I've definitely included acoustic insulation the floor of the first level. This insulation for this is R1.7 - do you think this is sufficient? I've been thinking I might need to upgrade this, especially because we won't be having carpet on the first floor so I'm particularly worried about noise being an issue. Re: Insulation questions 12Dec 16, 2021 8:15 am strannik R1.7 is thermal rating, for acoustics you need to look at Rw values. We have carpets but it doesn't help much. Ok thank you! Re: Insulation questions 13Dec 29, 2021 4:35 pm From memory R2.7 insulation batts were nearly twice as expensive as R2.5, it's crazy money considering slight increase in insulation value. I say stick with the 2.5. Re: Insulation questions 14Dec 30, 2021 8:16 am Heliosphere From memory R2.7 insulation batts were nearly twice as expensive as R2.5, it's crazy money considering slight increase in insulation value. I say stick with the 2.5. Thank you, that’s very helpful. Seems pretty clear that the ROI is not worth upgrading to R2.7. 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 11279 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 6210 |