R-50 wall construction: Double 2×4 stud vs. single 2×6 with exterior XPS
Are there any good reports using actual construction experience comparisons for the cost to build double stud 2×4 (or 2×6) walls compared to single 2×6 with exterior insulation?
Also, most of the articles I’ve read regarding double 2×4 walls use 24″ OC. I would think for the minimal cost difference to stay 16″ OC you get better drywall finish, and shear wall capacity for 2 storey construction.
Wondering if there is a recent (within the last 2-3 years) comprehensive report that has evaluated material costs, construction labor, advantages/disadvantages, etc. of all of these factors.