3 layers of Roxul vs. 1 and foam.
So I’m trying to come up with a wall insulation that will work with my budget and prefer DYI.
I’ve priced Roxul as I like its qualities and come to the conculsion that putting 3 layers of R16 2×4 16o.c. is cheaper than 1 layer of Roxul R22 or R24 2X6 16 or 24o.c. and 4″ of Pink ridged foam on the exterior. I know the lumber and labor of a double stud wall will cost more. (pricing that currently)
I would like to know if the 3 layers of R16 Roxul will perform well in this stack up compared to the 1 R22 plus exterior foam idea. Will it actually get R48 or will whole wall R-value be way down
Also would putting 1.5″ Comfortboard R6 on the outside help in anyway?
House located in Toronto ,ON Zone 6
Thanks for any input