Wonder

Research Outline

Prepared for Rodney C. | Delivered January 16, 2020

Accessory Dwelling Unit Programs

Goals

To obtain a list of states in the continental United States which offer accessory dwelling unit programs, along with a link to the details of the program/ordinance and information on design and size requirements, the permitting timeline and process, and parking and lot size requirements. 

Early Findings

While a number of states have accessory dwelling unit programs, the rules appear to vary from one city to the next. This means that while certain areas of a state may allow for ADUs, other cities or areas may not. 
The website accessorydwellings.org has compiled a list of cities and states with programs allowing for accessory dwelling units, along with links to additional details about those programs. 
Of the states listed, California appears to have the most ADU programs, with over 80 cities and counties listed in total. 
Minnesotta also has a number of regions with ADU programs, including 15 in total: Apple Valley, Bloomington, Eagan, Inver Grove Heights, Lakeville, Minneapolis, Minetonka, Northfield, Plymouth, Richfield, Roseville, Shoreview, Stillwater, and White Bear Lake. 
Alternatively, New Hampshire has a statewide law allowing for accessory dwelling units.
In other cities - such as Dallas, Texas - the units are only allowed for under special provisions; whereas other cities or states - such as Chicago, Illinois - allow for existing ADUs to be grandfathered in but have banned the addition of new ones.  
While not every city or state has a law in place concerning the addition or use of accessory dwelling units, their use has recently been rising in popularity throughout both the United States and Canada. This fact may lead to the creation of new laws or ordinances throughout cities, counties, and states throughout the United States. 