What the county actually requires, who to call, and where people get caught out.
No formal opt-out program, but the closest thing to barely-regulated rural Arizona: the county adopted the plain 2015 IRC 200 sq ft exemption (verified from its own handout), runs a tiny one-office department, is repeatedly described by off-grid builders as the most reasonable and alternative-building-friendly county in northern Arizona, and enforcement in its vast rural areas (Concho, Sanders) is famously light — though a dome over 200 sq ft or a habitable studio still legally needs a permit.
Call the office above and describe your actual build. Two things catch dome builders out in every Arizona county, whatever the permit light says: septic is regulated by the state regardless of what the county does about buildings, and no permit means no certificate of occupancy — which usually means no conventional mortgage and no standard homeowner's insurance, and a cash-buyers-only sale later.
Snow load is the other one. At elevation in Arizona it is a real engineering number, not a formality — the calculator works it out for your site.
Work out your dome's struts, hubs and cost →
This is a plain-English summary of published county rules, gathered for Tom & Courtney's Desert Domes — it is not legal advice, and codes change. The county office above is the authority; confirm with them before you buy materials.