We’re designing and planning a two story house in North Florida (CZ 2/3 border). The house is currently designed to have the lower story be clad in traditional cementitious stucco and the upper story to be fiber cement siding over 2×6 construction and a monolithic slab on grade foundation.

We’re considering building the exterior walls out of Durisol. I really like the idea of this kind of product over traditional ICF. But I have a few questions to know whether or not it would work:

1) The versions with the mineral wool inserts seem like you’re sacrificing structural strength for little squares of insulation.. Wouldn’t it make more sense to get the version without the inserts and just use continuous external insulation in our climate zone?

2) I do love mineral wool and would much rather use it over XPS or polyiso if I can. But I can’t figure out a good external wall assembly over Durisol. If we use the as-designed claddings, it would need to support stucco on the bottom story and I would want it to have an air gap and waterproof drainage plane.

So my options are: figure out how to design the exterior wall to support stucco and then have fiber cement on the upper story, using (preferably) rock wool or (alternatively) XPS, or have the whole house be clad in fiber cement, which would be easier to support having rock wool on the outside..

Your comments are appreciated. I’ve read all of the articles from BSC and GBA that I could find, but alot of them either applied to much colder climates or applied to wood/OSB walls. So I was hoping to get some specific advice using Durisol.

Thanks.