WI AB449

Political subdivisions with zoning ordinances must allow at least one accessory dwelling unit (ADU) as a permitted use on any residential or mixed-use parcel with an existing single-family dwelling, without requiring conditional use permits, variances, or special approvals

ADUs may be within, attached to, or detached from the main dwelling, and may be created by converting existing structures; must have a separate entrance and provide complete independent living facilities

Local governments retain authority to limit ADU size to no larger than the existing single-family dwelling, cap height at the zoning district maximum, and require compliance with setback and lot coverage requirements

Municipalities may prohibit newly created ADUs from being used as short-term rentals after the law's effective date

Takes effect on the first day of the 7th month after publication