What’s an ADU? An ADU is an Accessory Dwelling Unit… a self-contained dwelling on the same property as an existing single-family home containing at least a bedroom area, a kitchen area and a bathroom. They are similar to ‘granny flats’ that were common in the 1940s-1950s or ‘mother-in-law’ apartments found in the Twin Cities.
They have become more popular with rising housing costs, single-parent and single-person households, and with our aging population. Properties with two residences, one large and one small, offer many options to modify living arrangements as needs change. They can be a good option for multi-generational living for all ages.
ADUs can be ideal for grandparents to be close to family and still maintain independence while providing support back and forth.
ADUs can be great for adult children to move ‘back home’ but still provide privacy for both parents and children.
ADUs can be a good way to supplement income for all stages of life, from first-time homebuyers to retirees.
Areas are popping up throughout the country that are supportive of ADUs and it is estimated that there are currently about 25,000-100,000 permitted units and several million un-permitted ones. California loosened its restrictions in 2016 and the number of permits increased from 90 in 2015 to nearly 2,000 in 2017.
Minneapolis passed an ADU Ordinance in December 2014.
Minneapolis ADU requirements include…
- ADUs can be located inside a house, attached to a house or detached from one.
- If they are detached, an ADU cannot be larger than the main house or 1,300 square feet — whichever is smaller, including garage space.
- The unit also cannot be taller than the main house.
- The two units must be tied together with shared water, sewer and gas service.
- And the owner must own both houses and cannot rent out more than one.
In the first 3 years after passing the ordinance there were 92 ADU building permits issued in Minneapolis. Perhaps part of the reason there aren’t more is that many people don’t know about them. Perhaps another reason is city lots tend to be small, and it’s Minnesota so garages are taking up the space where ADUs could ideally be located. Double-size lots would be ideal for ADUs.
St. Paul passed an ADU ordinance in 2016, but at the end of 2017 only one permit had been approved.
It will be interesting to see how long it will take for the ADU concept to spread to the suburbs and beyond. I have a client who would love to have it extend to St. Louis Park. New Hampshire is the first state to institute statewide ADU-friendly legislation.
Want to learn more about ADUs?
Accessory Dwellings – a one-stop source about accessory dwelling units, multigenerational homes, laneway houses, ADUs, granny flats, in-law units…
What’s all the fuss about ADUs? – issue of The SRES Professional dedicated to ADUs
- Inside one of Minneapolis’ first, and coolest, accessory dwelling units – from StarTribune
- Accessory Dwelling Units: A Tale of Two Cities – comparison of ADU legislation in Minneapolis and St. Paul