Pitkin County building permits start before the structure

Small does not automatically mean permit-free. Building permits are required for residential and commercial structures regardless of size or use, so the dividing line is not square footage. It is whether you are putting up a structure at all.

That sweeps in far more than a new house. A shed, a gate, an accessory building, a shop, a remodel, roof work, or a manufactured-home installation can each raise a permit question. And in a mountain county the building permit rarely travels alone. It can pull in zoning, access, wildfire, septic, drainage, or a referral to an outside agency, so a single shed can touch several reviews at once.

The Building Department handles code questions, plan review, inspections, and the permitting process itself, and the planning applications page is where the permit types and the construction documents each one needs live. So call before ordering materials: say what you want to build, where it will sit, and how it will be used. The Building Department can tell you which permit applies and whether any of those other reviews come into play.