We are building a new home in Zone 5(IN). We are considering the use of Zip-R sheathing with the 1″ foam section. The majority of our walls are 2×4 framing, but there are a few sections that are 2×6 for bearing. What would you recommend for the cavity insulation? Right now we have flash and batt plugged in (.5″CCF + R-13or R-19 batts depending on wall thickness). Does the “flash” and Zip-R foam act as one layer to alleviate concerns about dew point inside the wall in the 2×6 area?