St. Louis Ordinance 72036 establishes a specific ADU path in the A Single-Family District. The selected standards below must not be applied to other districts without checking current code.
Local standards
The selected local standards are summarized in the Ordinance Number 72036 (combined ordinance), Board Bill 60. The ordinance allows one ADU per parcel for the principal dwelling types it identifies. Maximum area is the greater of 50% of the largest principal dwelling’s area or 750 square feet, capped at 1,200 square feet. The stated maximum height is 25 feet, and a three-foot side-lot distance applies.
Confirm the applicable rule
The ordinance also limits front placement by the average front-yard line and gives a detached-building separation condition of at least 10 feet from the dwelling rear and nearest wall of an accessory structure. It describes some existing-foundation and nonconforming-structure cases subject to conditions. Confirm the ordinance’s current codification, applicable district, and parcel status before relying on these selected values. Zoning measurements do not by themselves establish fire separation, building-code compliance, utility capacity, or permit approval. For shared measurement methods, see the setback and separation guide and floor-area guide.
