This product looks very interesting. With an insulation value of R20 instead of thermal bridging and a great increase in load handling the small increase in price should easily be offset by the gains.
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You can use 16 or 24in centers with staggered studs. The method im talking about is essentially a double wall ,you using more studs, not less. What your staggering is the stud placement between the outside wall and the inside. But yea i like a 1 in sheet of foam in addition to the wall insulation more than any of these alternate stud plans. With just dense pack cellulose in the wall and ceiling i was able to eliminate all the baseboard in a large 8 by 9ft bathroom. Room stays same temp as the rest of the house. I put a switched 500 watt infrared heater in the ceiling just to bring it up above the house temp when the shower is in use.
Yes, that is how my BILs house is built, but this T-Stud process is less labor and materials intensive and evidently stronger too.Can achieve the same effect just staggering the 2x4s .Use a 2x6 plate and 2x4s along the outside and also staggered along the inside leaving a continuous void in the middle for wiring and blown insulation.
The best value where im at is the 1in.DOW pink foam 1/2 is $15, 3/4 is $17 and one inch is $20 a sheet. From there it goes way up for 1.5 inch at $32 a sheet. Best if its installed on the outside but it can be installed on the inside. I normally dont do this as the dense pack cellose alone is very effective. If i were using fibreglass batts(which i dont use) i would definitely consider additional insulation.What's the average price for 1" foam boards? Is this a polyiso or polystyrene type? I'm trying to learn as much as I can about this stuff before we do the inside of our house.
The best value where im at is the 1in.DOW pink foam 1/2 is $15, 3/4 is $17 and one inch is $20 a sheet. From there it goes way up for 1.5 inch at $32 a sheet. Best if its installed on the outside but it can be installed on the inside. I normally dont do this as the dense pack cellose alone is very effective. If i were using fibreglass batts(which i dont use) i would definitely consider additional insulation.
I am far more of fan of stress skin construction for new or my renovation approach which is put 1/2" of isoboard under the dry wall. Its quite noticeable how the cold spots from the studs thermal bridging is minimized with 1/2 inch of foil faced foam on top of them. The last reno I did was flash and bat with 1/2" of iso foam under the drywall. I haven't had an IR camera to check it but take half the baseboard out of that room wit no noticeable effect.
I dont think it would make any difference at all. I cant see the foam collapsing under the drywall. Plus the Foam board fasteners are right under the drywall as well.I would have thought that the insulation board behind the drywall would not be a strong enough base if someone were to lean up against it or something.
I use adjustable electric boxes. They have depth adjusting screws right in the face,can adjust out an extra inch at least. Yes always use at least 1/2 in drywall. 5/8 is stronger and is Fire Rated as well but very heavy. 3/8 is only for use over a solid material like plaster walls IMO. They make special nails with large washer for fastening foam board. You can buy these where you get the board.Its pretty simple. The biggest hassle is the electrical boxes. You can either use standard boxes and space them out from the wall to account for the extra thickness or you can buy box extenders that screw onto the face of the box. I use 1/2" foil faced isoboard which is pretty dense and the foil tends to spread point loads out plus the dry wall works .
Thanks for this tip! I'm looking into replacing the majority of my outlets and boxes soon. Any tips on exterior outlet boxes? I just removed one that was spliced into a kitchen outlet.I use adjustable electric boxes. They have depth adjusting screws right in the face,can adjust out an extra inch at least. Yes always use at least 1/2 in drywall. 5/8 is stronger and is Fire Rated as well but very heavy. 3/8 is only for use over a solid material like plaster walls IMO. They make special nails with large washer for fastening foam board. You can buy these where you get the board.
Well, I guess that answers the question then. Is there anything else we can do besides insulate the stud cavities?I dont think foam can be installed inside a living space without dry wall on top of it, if there is a fire the foam puts out toxic smoke.
Rockwool Comfortboard 80 exterior insulationWell, I guess that answers the question then. Is there anything else we can do besides insulate the stud cavities?
Rockwool Comfortboard 80 exterior insulation
https://www.rockwool.com/a/s/comfortboard-exterior-non-structural-insulation/
Are your stud cavities 5.5 in or 3.5in ? If 3.5 you may need something more get to the required wall R value. May need at least R30 walls or more in Maine .Even a 6in stud walls plus one inch of foam is only roughly R29 since rock wool is about R23.Well, I guess that answers the question then. Is there anything else we can do besides insulate the stud cavities?
It just needs to be covered not nessecarily with drywall.I dont think foam can be installed inside a living space without dry wall on top of it, if there is a fire the foam puts out toxic smoke.