June 13, 2019
On June 18, the County Council will discuss zoning code changes that support “Accessory Dwelling Units.” Here’s some important information I want to share with you.
Starting with what ADUs are and what they are not: An ADU is not the same thing as renting out a house or renting out rooms in a house. An ADU is a private residence inside of a house, such as a basement apartment; or a backyard cottage or garage conversion.
A detached ADU in green on the left
To get an ADU construction permit and license, the unit must have separation and privacy from the house as well as its own kitchen and a bathroom.
There are about 160,000 owner-occupied single-family detached homes in the County and about 15,000 rented single-family detached homes. But there are only 475 ADUs.
ADUs are a more targeted housing solution because they require owner occupancy on the property. That requirement puts some organic limits on ADUs as the arrangement has to be something that the homeowner welcomes as part of daily life.
Because ADUs require a kitchen and bath and a separate entrance as well as possibly on-site parking, ADUs require considerable construction. The cost of that will depend on a lot of factors, similar to any home renovation project. A modest basement conversion could be less than $50,000, while a backyard cottage could be 3 or 4 times that amount.
Benefits of ADUs
More affordable housing
ADUs are generally smaller than houses so they are more affordable as rentals. A 900 square foot basement apartment or a 700 square foot backyard cottage will rent for a lot less than a house. As a result ADUs can promote economic integration and diversity in communities by providing access to smaller and more affordable housing in otherwise very expensive areas.
Aging in place
ADUs can enable older, modest-income homeowners to age in place with a new source of income by renting out the ADU or by living in the ADU and renting out the house.
Families living together
ADUs are also a desired solution for parents seeking a way to live with adult children or with grandparents. While they certainly can all live in one house together with no ADU, having separation and privacy from an ADU while living together is for many a more appealing and affirming arrangement, including for families with an adult child with disabilities.
A final benefit of ADUs is that they add housing where there is already infrastructure. The impacts of these units are dispersed across a County that already has about 369,000 housing units in total.
What changes are proposed?
Unfortunately, the County’s zoning rules generally treat this housing type as a nuisance to be avoided rather than a resource to be welcomed. Our byzantine restrictions are a large reason the County is only producing a few dozen ADUs a year, a pittance compared to communities that have embraced them and create several hundred per year. This zoning change aims to change that framework.
Montgomery County zoning laws essentially prohibit backyard cottages or detached garage conversions. The code requires a property owner to have at least one acre in order to build one. Homeowners with an acre are the property owners least likely to need one and they don’t build them.
The proposal before the Council, as amended by the Planning and Housing Committee (where I serve as Chair with Councilmembers Andrew Friedson and Will Jawando), would limit the size of backyard cottages in a thoughtful way. The proposal limits the size of new cottages to 10% of the size of the lot.
In other words, if you have a 6000 square foot lot, the maximum size cottage you can build is 600 square feet.
Existing structures (typically garages) are exempt from this rule, as they already exist and there is no additional visual impact of the structure. They would have to meet code, of course.
Basement units are allowed to be the same size as the basement of the house, whatever footprint that may be.
In the existing County code, interior ADUs (typically basement apartments) cannot be closer than 300 feet to the nearest other ADU. This restriction basically limits them to one per block. The Committee proposal deletes that restriction, seeking to be supportive of ADUs.
To address concerns about parking, the Committee proposal requires ADUs that are farther than one mile from Metro or the Purple Line Station to build an additional parking space on the property or apply for a waiver based on available street parking.
As for setbacks and height restrictions and storm water, the proposal does not change any of those rules from the existing code for accessory structures — the rules that exist for homeowners who might want to build a separate garage or studio or guest house on their property, for example.
While some say we should have stricter rules for ADUs than garages, I don’t share that view.
What protections are provided?
I recognize that there are some residents who find this housing solution problematic. If you are among them, please consider the following.
First, owner occupancy is a requirement. The owner must live on the property. That naturally constrains how the ADUs will be used. For example, an investor can’t purchase a house, add an ADU, and then rent out both units.
More generally, a property owner is only going to allow a property to be used in a manner that the owner is willing to live with personally. The historic Town of Brookeville which strongly supports ADUs has noted the benefit of the owner occupancy rule.
Prohibition of short-term renting and other rental limits
Another key point is that the units may not be rented out as short-term rentals (i.e., Airbnb). Montgomery County homeowners are allowed, under certain circumstances, to rent out their homes or rooms in their homes on a short term basis. That right would not extend to ADUs.
Any homeowner who wanted to rent out the bedroom from an ADU on a short term basis would have to remove the features that make it an ADU, such as kitchen equipment or even the internal separation from the house.
As a result, space built for an ADU would have the same short-term rental value as any other spare bedroom or underutilized living space.
Another significant restriction is that no other rental would be allowed on the property. So an owner could not also rent out the main house or rooms in the house.
Inspections and code enforcement
ADUs have license and inspection requirements. Licenses can be taken away for noncompliance, and penalties can be significant.
Finally, after hearing from some neighborhoods about general crowding of housing and concerns about the capacity of the County to conduct ADU inspections, the Council just added 3 code enforcement positions to focus on inspections in residential neighborhoods. Those positions will be hired soon.
What about schools?
One of the common questions asked about expanding ADUs is about the impact of this new housing on schools. Given that many schools are crowded, it is a natural concern.
To find out the answer, our Planning department pulled the list of all the licensed ADUs in the County and cross checked the property address with school enrollment data at MCPS.
What they learned is that properties that have a house and an ADU have no more students on average (0.464 students per address) than properties with just a house (0.462 students). To be clear, the data point compares the house and the ADU combined, versus properties with just a house. There is no difference in school enrollment.
Given the owner occupancy requirement, this should not be surprising, when you think about it. A property owner with a family might bring in grandparents or a tenant; or a retired couple might bring in a young family; but for one family on a property to add a second family as a tenant would have a big impact on that first family. That’s why it doesn’t really happen.
I find this data to be highly persuasive that ADUs are exactly what we have suggested they will be: a tailored housing solution that makes a very big difference in small targeted ways.
What is the process from here?
On Tuesday, June 18, the County Council will hold a worksession on the Committee’s recommendation.
The Committee met 3 times in March and April to work the issue through, following a public hearing in February. The Planning Board also conducted a public hearing and worksessions.
Presumably the Council will consider amendments raised, if any, and then come back at a later date to vote.
Thanks for reading. If you have made it this far and have any further questions, please don’t hesitate to ask.