St. Peters, MO Accessory Structures: Garage Conversions (2026)

Under Section 405.130(J)(1), the City of St. Peters, Missouri directly restricts what homeowners can do with an original garage: in any single-family home constructed to originally include a garage, that garage cannot be removed and must continue to be used as a garage, and it cannot be converted to living quarters. This applies across all single-family residential developments in the R-1 district, not only to new construction. For lots platted after July 1, 2000, the code goes further and requires a two-car garage with a minimum width of twenty-two feet; a builder may instead provide a twenty-foot-wide garage only if one additional foot of depth is added for storage or to accommodate extended vehicles.

Every garage covered by this section must include doors capable of closing, ruling out an open-bay or carport-style conversion in place of an enclosed garage. The rule sits in the same Miscellaneous Requirements subsection as St. Peters' farm equipment parking rule, which limits parked farm equipment in R-1 to lots of at least two acres, and its outside storage rule for barbecue equipment, lawn mowers, and heavy equipment. The Planning, Community and Economic Development Department's Neighborhood Preservation staff enforces the garage requirement through code enforcement inspections, and a homeowner who wants to repurpose a garage as a bedroom, den, or home office in violation of this section has no administrative path around it within Section 405.130 itself.