I am in the planning phase of building a home in the NJ-NY area, Climate zone 5. As I investigate my options; SIPS, double wall stick 2x4 wood, 2x6 wood, ICFs, CMU, Larsen trusses, etc.. and the myriad of permutations to insulate each one (spray foam, cellulose, hybrid batt & flash, exterior rigid foam/iso panels, etc....) I came across STEEL. My goal is as high R-value as I can get within reason $$, with hope of upwards of R-30 final values. That said, I need some objective input.
Steel seems like a really good option. Almost unheard in my area, despite being upwards of 60% recycled, lasts forever (relatively speaking) super strong, straight, minimal waste, not affected by termites/pests or mold, equal or close to wood in cost (depending who you ask). I know it has very high thermal conductivity. However there are configurations that can abate this significantly (braced walls with double layer of external 2" poly-iso taped & staggered seams as sheathing, +/- flash SPF to give the wall more rigidity tieing it all together). Why isn't it more popular? Am I missing something? Thank you kindly for any thoughful input.