Lee's Summit, MO Accessory Structures: ADU Owner Occupancy (2026)

The Unified Development Ordinance's ADU permitting and occupancy rule has four parts. First, at the time of the building permit application the applicant must attest to owner occupancy of the premises where the ADU will sit. Second, ongoing owner occupancy of either the primary dwelling or the ADU is required for the life of the arrangement, though the Director may grant a temporary waiver of up to one year when the owner-occupant has a documented need to leave, such as a job relocation, illness, or similar circumstance.

Third, the primary dwelling and the ADU must remain under single ownership, so the two units cannot be split into separate titles while the ADU exists. Fourth, the ADU must meet all adopted building and fire code requirements and is assigned its own separate address, which matters for emergency response, mail, and utility billing. These occupancy conditions sit on top of the broader ADU eligibility rules: an ADU is only allowed on lots in Old Downtown Lee's Summit, on half-acre-or-larger lots zoned AG, RDR, RLL, R-1, or RP-1, or on lots approved through the Preliminary Development Plan process, and only one ADU is permitted per single-family lot.

The stated purpose of the ADU program is to promote efficient land use and add affordable housing options while preserving the single-family character of the existing residence and neighborhood.