Senate Bill 473 mandates that political subdivisions with zoning ordinances must permit at least one accessory dwelling unit (ADU) on each residentially or mixed-use zoned parcel that contains an existing single-family dwelling. The bill defines an ADU as a residential unit that provides independent living facilities and has a separate entrance from the main dwelling. It allows local governments to impose certain restrictions, such as limiting the size of the ADU to the square footage of the existing single-family home, regulating its height, ensuring compliance with setback and lot coverage requirements, and prohibiting the use of newly created ADUs as short-term rentals.

The bill introduces new statutory provisions under sections 59.69 (16), 60.61 (3o), and 62.23 (7) (j), which outline the definitions and requirements for ADUs. Each section emphasizes that the ADUs must be permitted uses without the need for conditional use permits or variances, while also allowing local ordinances to set specific limitations. The legislation aims to enhance housing availability by facilitating the development of ADUs while maintaining local zoning authority. The act is set to take effect on the first day of the seventh month following its publication.