Accessory apartment over garage in Seattle. Photo by studio-d on Flickr.

Citing increased housing costs, Montgomery County planners want to make it easier for homeowners to add accessory apartments or “granny flats” to their property and rent them out. While the new policy is a step in the right direction, balancing neighbors’ concerns with the need to provide more housing in high-demand areas will be a challenge.

Last week, the Planning Board approved a set of changes to the current policy, which the County Council will review this fall. Today, homeowners who want to build an accessory dwelling have to get a special exception from the county’s Board of Appeals, which requires a public hearing.

The new policy would allow accessory units in most of the county’s single-family zones. Homeowners wouldn’t need a hearing, but they’d still need to get approval from building officials to create an apartment, register the unit with the Department of Housing and Community Affairs, apply for a rental license, and renew the license each year.

Planners say allowing accessory apartments will help financially strapped homeowners cover their mortgages while providing additional housing choices for renters, particularly young adults, who are priced out of many MoCo neighborhoods. Accessory dwellings are already allowed “by right” in a variety of communities, from cities like Portland to suburban Lexington, Massachusetts to rural Fauquier County, Virginia.

Opponents fear “devastation”

Super-Addition, Nora Drive
Neighbors fear loosening restrictions will lead to more oversized additions like this one in White Oak. Photo by the author.


However, not everyone’s on board. WeAreMoCo, a newly-created citizens’ group, argues that not requiring a public hearing is undemocratic, while angry residents packed a meeting about the proposed change in May, claiming that it would threaten the character of single-family neighborhoods. In an e-mail to the Planning Board, Silver Spring resident Alice Gilson wrote that accessory apartments would “devastate our area” and eventually “lead to middle class flight.”

Some opponents argue that allowing accessory units is a bad idea because the county already can’t stop every illegal unit that exists. Many property owners do indeed choose to ignore the application process and rent out apartments without permission, and unknown to the county. Often, these units are poorly built or overcrowded, putting tenants in danger.

Others exist in a sort of legal limbo: the owner may get approval to build an addition with a bathroom but not a full kitchen, exempting them from the permitting process for apartments even as they rent the space out as one. Even legal units can earn the ire of neighbors for being oversized or unattractive, like this this 1,500 square foot “addition” to a house in White Oak.

On the other hand, how could you blame someone for building an illegal unit? The current system forces homeowners to defend their financial or household situation to wary neighbors, reducing the incentive to take the legal route. Residents may not want accessory apartments in their neighborhoods, but they probably prefer legal, vetted units to illegal ones with no regulation at all.

How can we ensure the creation of safe, context-sensitive accessory apartments? We need to streamline the approval process, making it less intimidating to property owners. But we also need to make the guidelines for what they can and cannot build clear and easy to follow, letting neighbors know what to expect when one gets built on their block.

What county planners propose

Kent Square at Selby, Kentlands
This accessory apartment in Kentlands (over the garage) is located on a 4,300 square foot lot, smaller than would be allowed elsewhere in Montgomery County under the new regulations. Photo by the author.


The proposed policy reduces the legal process required to build an accessory apartment, but it’s somewhat more restrictive than the current regulations regarding the size, number, and location of units throughout the county.

Today, homeowners can apply to build a unit as large as 2,500 square feet, but the new proposal caps unit size at either 50% of the main house, 800 square feet or 1,200 square feet, depending on the size of the house or the lot. The new rules also specify that a house with an accessory apartment has to be at least 300 to 500 feet away from another house with one in order to prevent the “overconcentration” of units. There’s also a limit of 3 residents per accessory unit, which didn’t exist before.

So-called “backyard cottages,” accessory dwellings in a separate structure from the main house, were only allowed on lots larger than 2 acres today. Planners were going to allow them on most lots in an earlier draft of the new rules, but they now suggest allowing backyard cottages only in rural zones with lots larger than one acre.

They also aren’t considering giving amnesty to existing unlawful apartments. Those who have them would have to apply for a permit just like everyone else.

The new rules won’t result in a flood of new apartments, as they would include a cap of 2000 accessory dwellings countywide. Today, there are just 380 legal accessory apartments and 548 “registered living units,” built for relatives or household employees who live there rent-free. Planners estimate that 0.2 to 0.5 new accessory dwellings per 1000 homes will be added annually. With 163,000 owner-occupied single-family homes in the county, that comes out to between 30 and 80 new units each year, compared to 10 today.

A cap on accessory apartments might assuage the fears of residents who oppose changing the policy. But for those who could benefit from this new source of housing, the new policy doesn’t do enough.

How could the rules be better?

location of accessory apartments
Most existing accessory apartments are located downcounty. Image from the Montgomery County Planning Department.


The proposed regulations make it difficult to build accessory dwellings in the areas where they’ll have the most impact, which hurts homeowners and renters. However, they should also offer more guidance as to how units are designed, addressing neighbors’ concerns about privacy, crowding and aesthetics.

Potential accessory apartment dwellers may want to locate in desirable downcounty communities like Bethesda, Silver Spring and Takoma Park, where housing is often more expensive but close to jobs, shopping and public transit. Not surprisingly, most of the county’s existing accessory dwellings are in these places. Encouraging more of them here would put these areas within reach of more homeowners and renters and ideally give them shorter commutes, reducing traffic congestion.

However, the proposed policy limits the number of units that can be created in these areas, by allowing only 2000 units in the entire county and requiring that they’re at least 300 feet apart. And because there aren’t any one-acre lots in these neighborhoods, the new policy won’t allow backyard cottages there, either.

Why should it be easier to build an accessory apartment on an acre in Potomac, far from jobs or transit, than in a neighborhood like Woodside Park in Silver Spring, where homes sit on generous 1/3-acre lots less than a mile from the Metro? They already exist on much smaller lots in neighborhoods like Kentlands in Gaithersburg, which isn’t under the jurisdiction of the county’s planning department.

Privacy in backyard cottages
Seattle’s Backyard Cottages Guide shows homeowners how to site an accessory dwelling on their property.


Opponents of the new policy might say that accessory dwellings will harm neighborhoods like Woodside Park, but clear, properly enforced guidelines can ensure that new units respect the existing context. Many places that allow accessory apartments offer clear directions on what homeowners can or cannot do. Vancouver, Canada has a “Laneway Housing How-to Guide,” which provides examples of accessory units that have already been built. Seattle has a 54-page guide to building backyard cottages, including sample layouts and directions on how to provide parking or maximize privacy. And Portland walks homeowners through the approval process, ensuring that their unit meets all regulations before they apply.

These guidelines should be made with public input so neighbors can help set the rules, rather than fight them in a public hearing. As a result, homeowners get a template they can follow, saving them time and hassle; neighbors know what kinds of additions to expect in their community; and tenants get safe, functional, and attractive places to live.

Accessory apartments give residents freedom

Opponents say that accessory apartments will hurt their single-family neighborhoods. But as Washington Post columnist Roger K. Lewis points out, many of Montgomery County’s single-family homes were built for large families. But as households shrink, many of these homes hold just one or two people today. A retired couple living in a four-bedroom house and carving out an apartment for their grandkids or an unrelated tenant isn’t “changing” the neighborhood, but bringing it back to the occupancy level it was built for.

Let’s face it: Montgomery County is an expensive place to live, and many households are struggling to make ends meet. Making it easier to build accessory dwelling units gives both homeowners and renters the freedom to live where they want and within their means. The county’s current policy doesn’t prevent accessory apartments from being built, but it does ensure that the creation of more illegal, unsafe, and unattractive apartments. That’s a status quo our residents and our neighborhoods can’t afford to keep.