Exterior insulation and garage
Salibonz
| Posted in General Questions on
I am preparing to build a new home in climate zone 6a. I am going to. E installing 2 inches of exterior gps foam boards. The home has an attached garage with bedroom above it. How do I air seal and insulatevthe wall adjoining the garage and living space, as well as to how do I deal with the ceiling of the garage, to air seal it as well.
I was thinking maybe frame the garage after the adjoining wall is zip sheathed, taped and exterior insulation added, and then tapping siga majvest to zip and attaching to the underside of the floor trusses as an air seal. Is this the typical protocol. Thanks for the help
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Since there is a bedroom above, even if you don't intend to insulate the garage, it will be insulated 'by accident'
Thus any energy penalty from the garage house interface will be minimal
Do you mean when I insulate the exterior? How do I address the wall separating the garage from the living space? There will be 2 walls to deal with. Do i zip sheathed it,tape and seal it and then add 2 inches of insulation? And continue it to the ceiling separating the garage from living space? Also would I still need 2 layers of 5/8" rock for fire rating?
The best approach is to fully build, wrap and air-seal the house, then build the garage. That way you have good air separation between the two. You can add the exterior insulation at the house before or after building the garage, depending how stringent you want to be about thermal bridging. Drywall used for fire ratings usually has to continue to the roof sheathing, unless the garage ceiling and other walls are fully fire-rated instead.
Ok sounds good thank you.
I dunno Michael, I think in terms of the shell being inviable. Build the shell to keep the weather out. The garage is part of that shell. It has a bedroom above, it has to be.
The garage will be insulated from the house, but unless there is some odd insulation strategy, the garage will end up insulated also
5/8 sheet rock in garage under will extend across ceiling, no?
Framer is not going to charge for coming back twice?
For what potential yearly savings?
A garage under is difficult to seal, but I see no advantage to framing after, and potential problems