Rammed Earth Tire (Earthship-style)

Peer Replacement — Retaining/berm wall replacement

Best shape: Berm / hillside, earth-sheltered · Tier: Any, labor-intensive

Moisture barrier always (standing MM rule), stucco/plaster cap on any exterior face, batter/step-back per course. Frost heave, now resolved: footing below the local frost line (WV frost depth runs roughly 24–36 inches depending on county/elevation — check the local figure, don't assume one number statewide), rigid exterior insulation on the berm-facing side extending down to the footing so the thermal mass wall itself never freezes, and a real perimeter drain at the footing — water sitting against the wall is what actually drives heave, not cold alone, so drainage matters as much as the insulation.

Frost heave: resolved, see keyRequirement above — standard Earthship-construction practice, well-documented, not actually in dispute. Off-gassing: still genuinely unresolved, not just under-researched by MM — vulcanized rubber is reasonably inert at ambient temperature once fully encapsulated (stucco/earth on every exposed face, no bare tire ever facing interior air), but independent long-term air-quality studies measuring actual VOC off-gassing (benzothiazole and other rubber-curing byproducts are the specific compounds of concern) inside occupied tire-wall structures over decades are thin, and Earthships intentionally heat this exact thermal mass with passive solar gain, which could plausibly accelerate any real off-gassing versus ambient-temperature tire storage. Full encapsulation remains the correct precaution either way; this entry stays unverified until a real study closes the question, not pending more MM research time.