Corrugated metal siding, mineral wool insulation, and flashing details

Hey fellas. So we’ve added a garage and an addition, It’s all zip or prosoco, and ready for finishes. I intended to do all cedar, but after watching the wildfires and being in the mountains, I think I’ll be going with metal other than easily accessible areas in the front of my home.
My first question is on comfort board. The house is 2×6 walls, with an inch or two of closed cell and fiberglass. Quite frankly I have so many windows I’m unsure if it’s going to be noticeable but I do see clear evidence of thermal bridging both with a thermal camera and on a really cold frosty morning outside. Adding R6 of rock wool looks to be about $4k plus the hassle. How do you go about that decision?
Second, the only thing I’m not thrilled about with the traditional corrugated installation is the way windows and doors are trimmed out. Rather than folding metal and ending up with some sharp edges and less than perfect details, have you ever seen trimming out with thicker gauge steel to keep nice edges everywhere? I’m assuming not since I can’t find many photos, but I’m up for suggestions as all these corrugated details will be on deck level.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part


Replies