Garage, Bonus Room, and Basement Insulation
I am in zone 5B
I have some questions on three different areas of my home before I OK the work to be done…
I am fully insulating & going to do a two-zone mini-split to serve the garage & the bonus room above the garage. I installed R-23 RockWool in the walls, covered w/ Membrain, and then 7/16” OSB.
My new home energy company slated to do the work are proposing to spray foam the common wall between the home & garage w/ 3” of closed cell that cures to ~R-7 per inch (R-21). They also proposed spraying the garage ceiling w/ 2” of closed cell to R-14 to insulate & help isolate garage from bonus room.
My question is I’d like some input on spraying another inch or two to the common wall with the house as well as 1-3 more inches on the ceiling. I’d like to keep any heat dumped into the garage there as long as possible & 2” on the ceiling seems “thin” to me…
Bonus room above the garage:
The original plan by the first contractor was to install Accuvents w/ 5.5” of closed cell from soffits to peak. That contractor was a disaster & I had to fire them before the work was done. The next contractor pointed out that the roof vent running the length of the room actually has tar paper over it, so it does not actually communicate with the outside air. (Don’t ask me, I just shook my head). As the vent is currently useless, he recommended the same 5.5” of closed-cell BUT to block off the soffits w/ 2×8’s and then spray the entire roof line in a sealed fashion as the roof vent is useless at this point. He stated “that is the way I did the bonus room on my house.”
My unfinished basement has no water leaks & has a perimeter drain system that works great at this point, but it gets pretty cold (frost line is ~5’ down). They want to insulate the entire perimeter w/ 2” of Thermax rigid insulation. Rim joists are already closed-cell spray foamed to R-21.
My question is: They stated if there are no leaks, then there is no need to apply any type of waterproofing agent to the walls before the foam boards are glued up. Do you all agree with that?
Thank you all in advance for your help…
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