ADUs offer multi-generational living

An Accessory Dwelling Unit (ADU) can provide flexible and affordable housing options.
They can be used to keep aging family members close, but in their own space.
Or, the homeowner can downsize and move into the ADU, leaving the larger home for a young family.
An ADU also works for young people moving into their own space, and for singles who want to stay connected while living independently.
It’s multi-generational family living, and Castle Building and Remodeling owner Loren Schirber sees it getting more popular.
He’s partnering with Minneapolis Garage Builders on a new initiative, ADU Builder Minneapolis, to help streamline the process for those interested in ADUs as part of their garages.

AN ASSET
The majority of interest in ADUs the Minneapolis Garage Builders and Castle are seeing comes from homeowners in Minneapolis, St. Paul, Edina, and St. Louis Park who are interested in the option for an aging parent who is considering downsizing or moving to a nursing home or assisted living facility. Adding an additional detached dwelling unit allows independence while being near family members, they point out on the ADU Building Minneapolis website. Alternatively, they are hearing from homeowners who want to downsize on their own lot and rent out their home for income generation. They are also hearing from those who wish to create short or long-term rentals in the ADU to generate additional income.
“If you compare, what’s the cost of putting mom in a nursing home or assisted living versus being close by? It is a much more desirable, and at the end of the day, you have an asset that has some value,” said Schirber.
AARP has a section on their website devoted to the topic and two free publications, “The ABCs of ADUs” and “A Step By Step Guide to Design and Development” available to download.
A guide created by The Family Housing Fund offers specific information for the Twin Cities.

CHECK ZONING AND CONSTRUCTION CODES
Schirber observed that as property prices increase, adding a smaller ADU to the same lot becomes more attractive.
He was first introduced to ADUs during a trip to Seattle, Wash. where high property values have led owners to consider higher density uses. Zoning laws there allow for the lot to be split between the main house and the ADU. Minnesota has been slower to build ADUs (there were 13 built last year in Minneapolis), but on the West Coast “these things are being built like crazy,” stated Schirber.
While recent zoning policies has codified ADUs in Minnesota and there has been a resurgence in this type of housing, they have always been around, known as carriage houses, granny flats, garage apartments, in-law suites, sidekicks, alley flats, basement apartments, cottages, and guest houses. In the Frogtown neighborhood of St. Paul, new immigrants would commonly build an alley house in the back of their lot while saving to build a larger home in the front, according to local historian Jane McClure.
Schirber cautions people that building an ADU isn’t necessarily cheaper, as prices for an ADU can range from $100,000 to $350,000. Adding onto an existing home is more affordable, but Schirber observed that most of the people he talks to want a separate structure to offer more independent living.
Most existing garages need to be torn down and a whole new structure built in order to have the necessary footings. Typical garages are built to code on a concrete slab and the footing only goes down one foot, which can’t support multiple stories. More substantial footings are needed to keep the structure from moving due to frost and damaging water, sewer, gas and electric lines, Schirber explained.
Each city has its own codes regulating how close to the property line a building can be (setbacks), how much square footage can be used on the lot by buildings, and other things like height, windows, parking and rainwater runoff. In Minneapolis, the detached ADU must be connected to the existing sewer and water lines, which typically involves digging a trench at a range of $5,000-$10,000. In St. Paul, the ADU must have its own connection, which costs $10,000 or more.
A detached ADU will also need its own heating and cooling system, which drives up the price as compared to an attached ADU, which might use the same system. Additionally, you may need to break up the concrete in the existing basement in order to get the new line tied into it.
Creating a design and getting an architectural plan is another cost that can range from $500 to $10,000. ADU Builder Minneapolis aims to cut the cost of that by offering several designs for customers. “If we can get these models locked in, it makes it a lot easier for people to be able to pursue a project if they don’t have to spend five grand on a feasibility analysis and plan. The new construction model, I think, might help unlock some efficiencies in the building and the cost side of things to make it more reachable,” said Schirber.
Some homeowners opt to decrease costs by their own sweat equity, managing some or all of the framing, roofing, painting, flooring, insulation, plumbing, heating, and electric. Or, they serve as the general contractor and hire out individual pieces of the larger project.
“I talked to somebody in St Paul who said, “Oh, we got a little ahead of ourselves,’” remarked Schirber. They put in the driveway and a slab, and then learned that the city required deeper footings and insulation.
“Don’t try to do it piecemeal, because there’s a lot of things that have to get figured out,” Schirber recommended.