That’s a solid idea, but it’s a chess match with the codes. First, you’ll want to check the local building code for wind load—those tables in Section 16.3 will tell you the required gage for a storm shelter, and the fine print about egress windows. Next, the “green” angle: you can’t just slap a green sticker on anything. If you’re using recycled steel, you need to prove the material came from a certified source; the certificate of compliance has to be on file. For concrete, look at the embodied carbon numbers—there’s a whole clause about using supplementary cementitious materials like fly ash. Then there’s the safety code: you’ll need a structural engineer to submit a design that meets the seismic and wind criteria, and the fire department will want to see a fire-resistance rating. If you use timber, be sure it’s seasoned per the fire code’s ASTM standard. And don’t forget the egress requirements—two exits, a maximum of 1.2 meters to the exit, and the fire-rated doors must meet the 60‑minute standard. The rainwater collection spreadsheet I keep on my spreadsheet: it can help you design a catchment system that feeds the shelter’s potable water needs during an emergency. Just make sure you reference the local potable water regulations; the fine print says the catchment must be a separate system with a minimum 2‑meter pipe to the storage tanks. If you can get a single‑story, reinforced concrete structure that uses recycled aggregates, meets those wind tables, and passes the fire rating, you’ll have a shelter that’s both storm‑ready and truly green. Keep an eye on the “green‑washing” clauses—those are where people lose the point.

Sounds like you’re on the right track—just remember that the wind tables aren’t just numbers; they’re the first line of defense, so double‑check the load paths in the design. When you certify the steel, keep that certificate handy for the inspection, because they’ll want to see the source and the material properties. And once you lock in the fire rating, it’s wise to keep a copy of the fire department’s approval with the site plan. That way, if any future tweaks come up, you’re already a step ahead. Good luck, and may the shelter stay sturdy and green.

Glad to help—stability is the foundation of any good shelter, both for people and the planet.

Sounds good, just keep everything tight and double‑check that every detail stays on the books.