The following is a detailed explanation and analysis by County Executive Marc Elrich of the major changes to zoning law proposed by Councilmember Hans Riemer:
There is a proposed amendment to the County’s zoning code that would fundamentally alter virtually all residential areas in the County now zoned for single-family detached homes. In a nutshell, ZTA 19-01, Accessory Residential Uses would delete several existing requirements that must be met by property owners who want to build an additional living unit on a lot zoned for a single-family detached dwelling. Yet as I have traveled around the County, I’ve discovered that most residents are either unaware of the proposed zoning changes or may not have a clear understanding of what they are.
Accessory apartments, also known as accessory dwelling units (ADUs) are allowed today in virtually all residential zones in Montgomery County. They can be built by converting part of an existing home, building an addition, or in some zones by constructing a free-standing unit in the back yard. They can answer the need for additional housing options, whether for extended families or as a source of supplemental income that makes homeownership more affordable for more people.
Although I supported recent legislation intended to encourage more ADUs in the County, I have questioned whether ZTA19-01 provides the right framework for addressing our housing needs while maintaining the quality of life that has attracted so many people to our single-family neighborhoods. Despite the rhetoric that ADUs are a tool for affordable housing, it is highly unlikely that they will help the extremely low-income households (defined as 30 percent of the area median income) that most need affordable housing.
Here are some questions and answers about the ZTA as approved by the County Council’s Planning, Housing, and Economic Development Committee (PHED). I hope you will have time to read this and share your thoughts with me, your civic and/or community association, and with councilmembers prior to their review of the legislation, scheduled for mid-June.
What problem is ZTA 19-01 trying to solve?
Councilmember Hans Riemer introduced ZTA 19-01 to encourage the creation of more ADUs (Accessory Dwelling Units) in single-family neighborhoods throughout Montgomery County. He and others see them as a means of producing additional housing options, including but not limited to affordable housing. (However, there are no requirements to ensure affordability.) Councilmember Riemer has explained that ADUs can be an apartment over a garage, a basement apartment, or a “tiny house” on a side lot or back yard – a second, separate living unit on a single-family lot, with a full kitchen and bathroom, and accessed by a separate entrance.
Are ADUs, including “tiny houses,” already allowed in Montgomery County?
Yes, they are. They can be built in, or as an addition to, an existing home and as a detached unit on lots of one acre or more. There are 414 licensed ADUs in the County; 356 of them (86 percent) are in the County’s smaller-lot residential zones found in areas like Wheaton, Silver Spring, Aspen Hill, Bethesda, Kensington, Takoma Park, Colesville, and Germantown. There are also unlicensed ADUs, but the County does not know how many.
Didn’t the Council make changes to ADU requirements last year?
Yes. Until last fall, ADUs were approved via conditional use (formerly known as a special exception) – a complicated, time-consuming, and sometimes costly process. To ease the approval process and encourage more ADUs, the previous County Council amended the zoning code in October 2018, removing the requirement for conditional use approval and allowing ADUs as a “limited” accessory residential use that meets certain standards. This change means that a homeowner’s application for an ADU can be approved as long as the ADU meets the standard requirements for parking, size of the ADU, and distance from other ADUs.
Is ZTA 19-01 needed so that I can have a separate unit for my in-laws?
Probably not. In virtually every neighborhood, your in-laws can have their own dwelling unit within your home, and depending on the zone you live in, you can construct a detached unit if you meet the conditions mentioned above. If your application for an ADU is denied because of parking or distance-separation requirements, you can apply for a waiver of those requirements through the process established in last year’s revisions to the zoning code. As a councilmember, I supported the changes made last fall because I believed they would provide more opportunities for ADUs without compromising the underlying intent of the County’s single-family zoning.
If the ADU approval process was just recently amended, why is this ZTA needed now?
That is a question I am wondering about myself. The Council made some important changes, but the changes are still new; they did not take effect until January 15, 2019 – the same day that additional changes were introduced via ZTA 19-01. While additional changes may be needed, such as adjusting the parking requirements, it makes sense to assess the effectiveness of the recent changes first and to do a better job of getting input from residents around the County about potential future changes. It also makes sense to have a companion bill that addresses related issues in the County’s code – issues that can’t be dealt with in a zoning text amendment.
Would ZTA 19-01 allow a detached ADU on any single-family lot regardless of size?
Yes. Current zoning regulations allow detached ADUs in certain “large-lot” zones on at least one acre. ZTA 19-01 would allow them in virtually all areas zoned for single-family detached dwellings, including areas where the average lot size is 6,000 square feet or less. This is a major Countywide change to single-family detached zoning, which currently allows homeowners to build an accessory structure in the back yard (i.e. a shed or other outbuilding) while ZTA 19-01 would allow a second, separate living unit.
What are the proposed size limitations for these detached ADUs?
Council staff summaries of the PHED Committee discussions refer to limiting the size to the least of “50 percent of the gross floor area of the principal dwelling or 10 percent of the lot area or 1,200 square feet of gross-floor area.” It isn’t clear whether gross-floor area refers to the footprint of the principal dwelling or the gross-floor area of all levels of the principal dwelling. The detached ADU can be up to 20 feet (2 stories) high. There is also a provision to allow an ADU up to 32 feet long (i.e. a trailer or manufactured home).
Will ADUs have an impact on already overcrowded schools?
If the intent of the ZTA is to encourage larger, family-sized units, it is possible that there will be an increase in the number of students. And although the owner of a newly built home must pay a school impact fee, a freestanding ADU for a family generates no fees.
Does ZTA 19-01 propose changing parking requirements?
Yes. Under the current zoning code, if two off-street parking spaces are required for the principal dwelling unit, one additional off-street space is required for an ADU. Homeowners can request a waiver of this requirement if there is adequate on-street parking. ZTA 19-01 would eliminate the requirement for one additional off-street parking space if the property is located within one mile of a Metro station or within the boundaries of the City of Takoma Park.
What happens if I live on a street with little or no off-street parking and I’m less than a mile from the Metro?
Parking may get very difficult in your neighborhood since there is no requirement and no assurance that the additional residents will not have cars.
What are the parking requirements in neighborhoods that don’t have driveways?
A homeowner who wants to convert part of the principal dwelling or build an addition or separate ADU would be required to build a driveway with two off-street parking spaces. This is true under the existing zoning code and apparently does not change under ZTA 19-01. It isn’t clear whether this can be appealed through the waiver process.
Can my neighbor build an ADU and then turn it into an Airbnb?
Yes, after one year under the existing zoning code and under ZTA 19-01. There is no language that requires a property owner to get approval for this change.
Are there potential environmental impacts?
In some cases, yes. There shouldn’t be any if an ADU is created within an existing dwelling unit, but environmental impacts can occur if an addition or separate dwelling unit is built in a back yard. Land disturbance during construction and the resulting replacement of green space with hard (impervious) surfaces means that less stormwater can be absorbed. This can lead to changes in the amount, velocity, and direction of rainwater runoff. Also, ground disturbance and construction can lead to the removal of trees or impacts to their root zones. There are no provisions in ZTA 19-01 that address these issues, although other jurisdictions that allow ADUs have requirements to protect and preserve trees and control stormwater runoff.
Why haven’t I heard about ZTA 19-01 before receiving this email?
Most ZTAs go through the review process without a huge public outreach component, primarily because most deal with specific, fairly narrow changes to the zoning code. There was a public hearing for ZTA 19-01, and shortly after its introduction in January 2019 Councilmember Riemer held a “community policy forum” inviting anyone interested in “reforming” the County’s existing ADU regulations to attend; most forum attendees were enthusiastic supporters of the ZTA. There were also three PHED Committee work sessions in March and April. For most residents, the County Council’s open meetings process is “inside baseball” – not something that they keep track of or follow on a regular basis. Recent comments from residents of the County’s suburban single-family neighborhoods indicate that very few were aware of these public discussions of the ZTA and are concerned because of its potential consequences. Some councilmembers have responded by reaching out to their constituents to get feedback on the proposed changes, but to my knowledge no other efforts have been made to expand public outreach so that County residents whose neighborhoods would be directly impacted by the proposed changes have the opportunity to weigh in on the recommended changes
Will ADUs provide affordable housing?
There is no specific language in this ZTA that assures that the rents for ADUs will be affordable; it is premised on the idea that the easier it is to add ADUs, the more housing there will be, and the price of that housing will be lower. Unfortunately, there is no evidence that this is how rental prices for ADUs work, primarily because construction costs are high, especially for detached units. It is also possible that allowing two dwelling units on any lot will drive up the value of the property and other homes in areas of the County that now offer a rich supply of affordable housing in modest-sized homes.
What are some of the best practices in other areas that allow ADUs?
Some jurisdictions in the DC area and around the country are embracing ADUs, but not without standards, programs, and processes to ensure their successful assimilation into single-family neighborhoods. Here are some of the best practices my staff and I have reviewed:
- Other jurisdictions have significantly smaller size limits (which may increase the likelihood that rents will be affordable);
- Several have robust information programs, education outreach, and even financial support to help with the high cost of building an ADU;
- Many have regulations on other issues – like stormwater management, tree protection, amnesty programs to encourage illegal ADUs to apply for licensing, design standards to encourage compatibility with the look and scale of the principal dwelling, a regular inspection regime, and incentives to keep ADUs from being converted from long-term to short-term rentals. Some of these could be addressed in ZTA 19-01; others could be wrapped into a companion bill that would revise relevant parts of the County code.
What changes will the full Council review in June?
The following provisions have been approved by the PHED Committee and will be reviewed by the full Council:
- Remove the current requirement for one additional onsite parking space if a property is in the City of Takoma Park or within one mile of a Metrorail Line station;
- Remove the minimum one-acre lot size for detached ADUs, thereby allowing them on any residential lot regardless of lot size – detached ADUs would be allowed in all residential zones including the smaller-lot R-60, R-90, and R-200 zones where they are currently not allowed (attached ADUs are allowed in all residential zones);
- Allow a detached ADU that is up to 32 feet long;
- Limit the size of ADUs located in the interior of a house to 1,200 square feet unless the proposed ADU is in a basement whose footprint is larger, in which case the ADU in the basement can match the larger footprint regardless of size;
- Limit the size to the least of 50 percent of the gross-floor area in the principal dwelling or 10 percent of the lot area or 1,200 square feet of gross-floor area.
- Delete the maximum size of an addition that can be used as an ADU (the current zoning code says that the maximum floor area used for an ADU in a proposed addition to the principal dwelling unit must not be more than 800 square feet if the proposed addition increases the footprint of the principal dwelling);
- Allow an accessory structure built before May 31, 2012 to be used as an ADU without regard to setbacks if it was legally constructed and there is no increase to the footprint or height of the structure; if an existing structure violates the setback standard, a new window on any wall on the side of the setback violation may not be constructed;
- Delete the distance requirement between ADUs;
- Delete the requirement that a house must be five years old before creating an ADU.
As I’ve indicated, I believe it is important to establish a responsive, well-regulated, and fair approval process for ADUs for property owners seeking alternative housing options, whether to address multigenerational needs or generate a source of income to provide mortgage relief or allow seniors to age in place. However, this is not a “one-size-fits-all” County, and how we achieve these goals matters if we want to successfully integrate a larger number of ADUs into our single-family neighborhoods. This is where you come in. If you have specific changes you would like to suggest or views you want to share about ZTA 19-01 or ADUs in general, please let me know by sending an email to Marc.Elrich@montgomeryCountymd.gov with “ADU” in the subject line. I also encourage you to share your views with councilmembers.
Thank you for taking the time to read this,