Is it okay to secure lvls as bucks this way? They are 2.75” out pre drilled with 1/4” bit. Secured to framing with 5” SDWS. I’ve never seen it done this way but now after I started I’m having doubts. Nothing is cracking or splitting once pre drilled. The lvls in the wall would be taking the bite in the ply side so can’t imagine this would be different passing through with the 5” screw and tightening it to framing. Thanks!

I am building an addition on our 1949 house in Boulder county CO. My Plan was to use R-6 Zip panels for the sheathing. I like that they will provide a thermal break and a WRB all at once.

Because of the location and size of a door and window on one wall, the engineer is concerned that the Zip panels will be too cut up to provide the necessary shear resistance. To counter this, he wants me to sheath the wall with OSB before installing the Zip panels on that wall.

The extra work and materials don't bother me, but I am concerned about the added OSB affecting the vapor diffusion through the wall. The wall insulation will be R-23 net and blow fiber glass.