St. Louis County, MO Parking Rules: RV & Boat Parking (2026)

Chapter 805 defines a house trailer broadly. Under § 805.010, a trailer is any vehicle or structure designed so that it permits occupancy as sleeping quarters for one or more persons, or the conduct of a business, profession, occupation or trade, and is mounted on wheels for use as a conveyance on highways. Travel trailers and camper-style units fall inside that wording. The chapter never mentions boats, and this page quotes no county rule written specifically for boats.

Section 805.110(1) bars parking any such trailer, occupied or unoccupied, on any lot or tract, improved or unimproved, unless it sits in an approved and licensed trailer camp. Subsection 2 adds the single exception: only one unoccupied trailer may be parked in an accessory private garage building or in a rear yard, and no living quarters may be maintained and no business practiced in it while it is parked or stored there. A trailer in a driveway or side yard does not qualify, and a second trailer on the lot does not qualify.

The other route is a permit to use the trailer as a place of abode under § 805.111. The applicant files plans with the Public Works Director, the original and five copies, showing the trailer location and drainage, potable water, toilet and bathing facilities, sewer connection, electrical service and the maximum number of people who will live in it. The plans must show compliance with the recognized setback line for the zoning district, and not less than ten (10) feet from any other building or vehicle or the boundary line of the tract. For zoning intensity, the trailer counts as a single-family dwelling. The filing fee is $25.00, plus $5.00 for each inspection after the first. The permit must be posted conspicuously on the trailer, departments inspect within 90 days of issuance, and the site is inspected again one year after issuance and each year after that.

Section 805.120 requires trailers to stay readily removable on their own wheels. Any attachment to a structure that limits ready removal converts the trailer into a single dwelling subject to the Zoning Order and Building Code. These sections reach unincorporated areas; incorporated municipalities such as Kirkwood or Ballwin write their own rules for their own streets and yards.