Type the number and everything below updates automatically.
⚙️ Builder options (hub gap, material length)
Every strut is measured point‑to‑point (center of one hub to the next). Real hubs take up space, so you cut each strut a little shorter. If your hubs eat 1¾″ total, put 1.75 here. Leave 0 if unsure.
EMT metal conduit usually comes in 10 ft sticks; lumber in 8–16 ft. Used to estimate how many to buy.
3Your dome
4Cut list — strut lengths
Lengths are point‑to‑point (hub center to hub center) unless you set a hub gap above. These are the standard Class I “Method 1” chord factors — but we don't take anyone's word for them: they're derived straight from the icosahedron (subdivide, project every point onto the sphere, measure) and re-checked against this app's numbers to five decimal places. Double‑check a couple of struts against a dome kit maker before cutting a whole pile. Do not cut any strut until your hub design is frozen — the hub gap changes every length. Ask me how I know, or better yet don't.
5What the struts will cost
Rough cost of just the strut frame for the dome & size you picked above — compared across the common materials. Changes live as you change the dome. Hubs, cover, screws & tax are not included.
Metal or wood only — struts are never plastic pipe. PVC domes look fine in the photos and sag by August. Approximate US shelf prices (July 2026), includes ~15% cut waste: 2×4 ≈ $5.50/8ft · 2×6 ≈ $9/8ft · ¾″ EMT ≈ $10/10ft · 1″ EMT ≈ $15/10ft · 1¼″ EMT ≈ $21/10ft · 1″ galvanized pipe ≈ $45/10ft. Lumber & metal prices swing a lot — confirm at your local Home Depot/Lowe's. This number is a planning number, not a promise, and lumber has never once apologized for moving. Metal EMT conduit is the usual best mix of strong + light + weatherproof.
6Where will it live?
Type a ZIP (like 86046 or 86442), a town, or your full address. The app figures out where you are and tailors everything below — weather, stores, permits, safety.
7Permits & city rules
Researched from each town's official code July 2026 and fact-checked, but rules change and lots depend on YOUR parcel's zoning — one phone call to the office listed above settles it for good. This is not legal advice — I'm a writer with a saw, not a lawyer. It's just the way we'd do it. And if the person who answers that county phone disagrees with this page, believe them. They're the one holding the stamp.
Real stores verified July 2026 (addresses & phones can change — call before a long drive, because out here a wrong turn is a two-hour turn). Tap the region buttons in Section 7 to switch towns. National mail-order sources are in the next two sections.
9Build it safe
10Frame kits & hubs (mail order, USA)
🔩 Hubs depend on your strut material — here's what to ask for. Conduit / pipe struts → steel hub connectors, sold as sets by dome frequency. You flatten and drill the pipe ends, or buy hubs the pipe slides into. Budget a few hundred dollars for a 3V set. Wood 2×4 struts → steel hub brackets for dimensional lumber — the boards bolt straight in. Sold as 2V/3V kits, roughly $600–$1,250 depending on size. Wood 2×6 struts, or a tight budget → cut your own ¾″ plywood gusset plates and bolt the struts to those. About $60–120 of plywood for a whole dome, and it's the cheapest hub going.
🤝 Why there are no dome-company names here. A few US outfits make these hubs and kits, and they're easy to find by searching the terms above. We don't list them — we're not going to hand a company free advertising on a page you're trusting for straight answers. If one of them ever pays us for the referral, it'll say so right here in plain English, and the advice above won't change one word.
Prices are rough guides gathered July 2026 — confirm before you buy. Metal conduit with steel hubs, or wood struts with lumber brackets (or your own plywood gussets), are the usual DIY combos.
11The cover / tent skin — what it should cost
🤝 No cover companies listed here — on purpose. Search "geodesic dome cover" or "dome tent membrane" and you'll find the handful of US makers in about a minute. What you won't find anywhere else is the number above: what a cover for your dome should actually cost, so you know whether a quote is fair before you pick up the phone. That's the useful part, and it's free. If a maker ever pays us for sending you their way, this box will say so out loud.
Covers are cut to each maker's own frame — confirm exact fit and final price before buying, and ask what the warranty is against UV. In this sun that's the whole ballgame.
12If this is a real home
Planning numbers for a permanent wood-framed dome home (not a weekend tent). Distilled for Arizona high-country and desert builds — not a substitute for an engineer or your county.
13Compare home sizes
Same dome type you picked in Section 1, side-by-side at the sizes people actually debate for a home. Highlight follows the diameter you set above (when you're in “width across” mode).
📄 Free: the Arizona Dome Permit Cheat Sheet
All 15 counties' permit lights, exempt square footage, opt-out programs, and the phone numbers — on one page. It downloads the moment you ask — the email is only so I can send you a heads-up when a county changes its rules. No newsletter, no spam.
14The one I already built
▶
Alaska, 2015. Electrical conduit, built by hand, filmed as I went.
🏔️ That dome held Alaska winters.
Conduit struts, no crew, no crane — one guy and a pile of sticks. It's the reason I
know the cut list on this page works: I cut one.
It's also the reason for the straight talk in Section 9. That dome would
never have passed a permit inspection, and I got lucky with the snow more than once.
Everything I'd do differently is what this site is made of.
15Ask me something
Building one of these and stuck on
something? Found a mistake on this page? Or you're a dome company and want to talk
about us sending you customers? This goes straight to me — there's no team,
it's one guy and a dog.
📬 What I can and can't answer.
Happy to talk cut lists, hubs, covers, which county is friendliest, what I'd do
differently, and what a quote should cost. What I can't do is tell you your dome is
safe to build — I'm not an engineer, and anybody who tells you otherwise over
email is doing you harm. For that you want a real one with a stamp.
One person reads these, so give it a day or two. Your email is used
to write back and nothing else — no list, no newsletter, never sold or shared.
