On Tuesday, Montgomery County amended its zoning laws to make it easier to build accessory apartments. After a year of research and about six months of discussion, the County Council unanimously approved ZTA 19-01 on Accessory Dwelling Units, which loosens restrictions for homeowners who want to build additional dwellings such as English basements or “granny flats” on their properties.
“We’re doing this because this is increasingly a way families want to live,” Councilmember Hans Riemer, the bill’s chief sponsor, said to WTOP. “Adult children want to be able to live with their parents or grandparents. Families want to be able to invite grandparents or adult children to live with them or to take in a renter.” Riemer said he hopes the measure will help people who are being priced out of the county.
Montgomery County, like much of the region, is experiencing a severe housing crunch, and affordable housing is especially difficult to come by. Accessory apartments can provide a secondary income source for homeowners and more affordable housing for renters. Some are used to accommodate returning adult children or to better care for aging relative. From an architect’s point of view, this zoning update allow us to help our clients better evaluate the feasibility of building one.
Questions of income distribution, demographic change, housing affordability and access, and more arose during the debate on this issue, and some of the rhetoric got ugly. Critics cited concerns about the units leading to strained public amenities like parking and schools, or worried they’d “change neighborhood character.” County Executive Marc Elrich released a letter back in March that acknowledged the county’s affordability issues but opposed the update anyway.
For context though, County Planning Director Gwen Wright said she’d be excited if the update produces another 100 accessory apaertments per year across the entire county. While the numbers remain to be seen, it’s true that residents are now more likely to see one pop up in their neighborhood or even in their own backyard. Here’s the nitty-gritty of what’s changed.
Breaking down the update
The approved amendment affected only a handful of clauses in the existing zoning rules, but the impact of a few of those changes is significant for a large swath of properties. Here are the most significant items of the new zoning regulation:
- Lot size: Before the amendment, accessory apartments had to be on a lot that was at least one acre. With the amendment, they can be built on lots from 6,000 square feet to 20,000 square feet (0.13-0.45 acre). Based on existing data, this affects about 30% of the county, and includes higher-density areas bordering DC like Silver Spring, White Oak, Chevy Chase, and Bethesda. Relatedly…
- Small lots: Small lots in single family homes (R-200, R-90 and R-60) couldn’t receive accessory apartments before, but after the amendment you can build in those zones so long as you respect all other zoning rules such as setbacks and lot coverage that are already in place.
- Distance: Before the amendment, accessory apartments were restricted to one every 300 feet. So, if a neighbor had an accessory apartment, no other neighbor could build one within 300 feet. This restriction has been removed, and now there’s no minimum distance between accessory apartments.
- Parking: Before the amendment, proposed accessory apartments had to create additional parking for potential tenants. With the amendment, there’s only a two off-street parking spot requirement.
- Age of the building: Before the amendment, the building had to be at least five years old to receive an accessory apartment. Now, new homes can be built with the accessory apartment already in the original building plans.
- Size: Before the amendment, the gross area of an accessory apartment could be no larger than 50% of the primary zone or 800 square feet, whichever was less. The amendment still restricts the potential size of an accessory apartment, but only relative to the property’s principal structure. It now allows for the habitable space alone to reach 50% of the main house’s size, with no fixed maximum.
The amendment didn’t change items that were already in place related to accessory apartments, such as the following:
- Numbers of accessory apartments: Only one accessory unit is allowed per lot.
- Height: Height restrictions for detached units depend on the residential zone where the property is located.
- Occupancy: A maximum of two unrelated adults can occupy the accessory apartment, but there’s no limit on the number of related adults that can occupy one.
- Entrance: A separate entrance for the accessory apartment is required. Specific location of the entrance can be placed were lifted with the amendment.
- Homeownership: The homeowner can occupy either the main house or the accessory apartment, but must live on the lot.
- Licensing: Accessory apartments must be licensed by the Department of Housing.
- Rental. Only traditional long-term rentals are allowed, not short-term ones (like AirBnB).
Based on the regulations outlined by the county, accessory apartments must follow all requirements set by the International Building Code and/or International Residential Code. This means that tiny houses like those featured on TV may not be allowed.
Building an accessory apartment is not trivial endeavor. Doing it in a way that benefits a community takes funds, much planning, and time. Now with the new policies in place, more renters and homeowners will be able to benefit from these more affordable housing options.