No ADU space does not mean no parking review
St. Louis’s ADU information says an ADU does not require off-street parking. It also says that if the project removes parking required for the primary dwelling, that parking must be replaced. Check the property’s required existing supply and the proposed work before treating the ADU exemption as the only relevant rule.
Show existing and proposed parking on the site plan, including any garage or driveway area that will be converted. Confirm how the City calculates required primary-home parking under the current zoning rules and whether the replacement can be located as proposed. Parking relief for the added unit does not establish that a driveway, alley, or emergency route is legal or usable.
Confirm utility routing for the detached unit
The City describes detached ADU water and electric utilities as typically tied into the primary structure. “Typically” is not a capacity or design determination. Ask the relevant utility and building reviewers whether a shared connection is allowed for this proposal, what calculations or inspections are required, and whether a new or upgraded service is needed.
Keep parking, utility design, provider capacity, and permit approval as separate decisions. The City information page is a local starting point; verify the current code and address-specific conditions before design or construction. For general checks, see ADU parking requirements and waivers and water, sewer, stormwater, and drainage.