accessory dwelling units, also called in-law apartments, by right in every community in the state in single-family zones. ADUs can come in many forms, including basement and attic apartments, additions onto existing homes, or small cottages separate from a main home.
Under the law, ADUs will not need local zoning approval as long as the units are the smaller of either 900 square feet or half the square footage of the primary home. Local laws on short-term rentals, like Airbnbs, will still apply, but "no municipality shall unreasonably restrict the creation or rental of an accessory dwelling unit," the law says.
