@christopherbwatkins92 Hello Chris,
Thank you so much for your great presentation! I learned a lot and really appreciate it.
Regarding question 1 of part 3, the question asked about the U-Value, but we added up all R-values, and our number 18.075 was an R-value, not a U-value. Also, it states the R-value of the full cavity is 19.
To calculate the U-value, do we need to do (1/18.075) + (1/19) = 0.6 U-value? Is this not the answer to the question? Could you please clarify this?
Thanks again!
Hi @sh.khodabakhshi,
I think you meant to tag @coachchrishopstock 
I’m glad you found his PDD Virtual Workshop: Exterior Wall Assemblies: Detailing & Best Practices helpful!
While the question asks you to calculate U-Value, the figures provided for each material is given in R-Value (which is typical in practice). You would first take the sum of all relevant R-Values from the worksheet (18.075). Then, knowing that U-Value is the inverse of R-Value, you would calculate 1 / 18.075 to get a U-Value of .055.
While the insulation is R-19, the actual R-Value of insulation + 6” metal studs @ 16” O.C. is 7.1 (as indicated in the worksheet). This component of the wall assembly is already factored into the R/U-Value calculation above.
Hope this helps!
Kiara Galicinao, AIA, NCARB
Product Coordinator
Black Spectacles