Can I Build Tiny Home in St. Louis, MO? (2026)

A tiny home is a small dwelling unit — typically under 400 sq ft — that can be built on a permanent foundation or on wheels. In St. Louis, MO, the rules differ significantly depending on whether the structure is on a permanent foundation (treated as a dwelling unit under building code) or on wheels (treated as a recreational vehicle under vehicle code). Tiny homes on permanent foundations must comply with local building codes in St. Louis.

Tiny Home Rules in St. Louis

Tiny Home Rules in St. Louis: Foundation-based tiny homes: Permit status not confirmed — see official source. Tiny homes on wheels (THOWs): Permit status not confirmed — see official source.

Costs & Fees

Building permit fees for tiny homes in St. Louis follow the same schedule as other new construction. Contact the local building department through their official website for current fee information.

Next Steps

Next steps for building a tiny home in St. Louis: 1. Determine foundation vs. wheeled — the rules are fundamentally different. 2. For foundation tiny homes, obtain a building permit from the local building department. 3. For wheeled tiny homes, verify whether your property allows RV siting. 4. Check if your tiny home could qualify as an ADU on your property.

St. Louis Building Division (Community Development Administration)

Frequently Asked Questions