Ok, I hope this is the best place to pose this question (mods, if its not, please move)
I'm building a walipini built on a foundation that kinda cuts the structure in half (half in soil, half with block walls with soil up against them), it will be more than 75% underground with the roof sticking up. My main question lies in my understanding of dry soil is insulative and wet soil is a heat sink, so I want to keep the wet soil off the outside of the block walls. Someone suggested that I put styrofoam insulation up against the block walls to keep them dry, but I had an idea of putting billboard vinyl underground at a slope away from the structure to run water away from it 5 foot or more (kinda like an underground roof on slope). It will have a sloped roof on it with an overhang of unknown size.
Anybody want to chime in with experience on this? I'm wanting to also know which would be best to put IN the blocks ; sawdust, perlite, styrofoam peanuts.....
Thanks in advance!