St. Peters, MO Zoning Overlays & Bonuses: Downtown Design Guide (2026)

Section 405.180 establishes the "S-D" Special Old Town Overlay District to preserve the integrity of Old Town as mapped on the Official Zoning District Map and to allow development consistent with the Old Town image and environment. The code expressly grants greater design flexibility here than under other district regulations, second only to the Planned Urban Development District, reflecting Old Town's mix of historic residential and commercial structures. Permitted uses under Subsection (B) include everything allowed in the R-1, R-2, C-1, and C-2 districts, plus outdoor flea markets, single- and two-family dwellings above a building's first floor, retail sale of used goods other than vehicles, and bed and breakfast establishments; hotels, motels, boarding houses, multiple-family uses, and body art or piercing establishments need a special use permit under Subsection (C).

Building and structure height is capped at thirty-five feet or two and one-half stories unless the Planning and Zoning Commission reviews and approves a taller design, and detached residential garages must meet the same accessory-structure size and height rules as the R-1 district. Because Old Town predates the city's planning and zoning framework, Subsection (F) sets no fixed yard requirement, instead requiring consistency with existing lot layouts and individual Commission approval, and Subsection (G) handles parking case by case against existing site conditions. Architectural guidance in Subsection (H) calls for modeling late nineteenth- and early twentieth-century design where feasible, with historic-styled signage permitted at C-2 commercial levels.