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Legalize two-family houses in Montgomery County

Let's say you own a house in Montgomery County and you're having trouble paying the mortgage. Or you have more space than you need and would like some extra income.

2-family house in New Hampshire. Photo by ilovebutter on Flickr.

If the zoning code is rewritten the way county planning staff proposed last week, you will be able to split your house into two apartments and rent one of them out ... if you are five feet seven inches tall, have red hair, and were born in West Virginia.

Actually, the limits proposed on so-called accessory apartments aren't quite that restrictive. But almost. Under the draft code, the following conditions must be met before a house can be divided into two units:

  • The owner must live in the larger of the two apartments. If work takes you out of town for a year and you want to rent out your house, you have to evict your tenants first.
  • The area of the smaller apartment must be less than 800 square feet.
  • You can't rent to a family of more than three.
  • There can't be another two-family house within 300 feet.
  • Each apartment must have its own outside entrance. The door to the smaller of the two apartments has to be on the side or back of the house.
  • You need at least three off-street parking spaces, covering at least 480 square feet of land. These parking spaces must be built without paving more than half of the front yard, even if the front yard is less than 960 square feet.
  • And when you somehow manage to meet all these requirements, if 1000 other people split up their houses before you, you're out of luck.
Some of these petty restrictions are already included in the present zoning code, which in addition makes homeowners go through a 9- to 13-month review process that includes public hearings. Only about 10 houses a year have been able to pass the tests. The county today has about 180,000 one-family houses, and only a few hundred two-family buildings.

This is simply absurd. Montgomery has an acute shortage of affordable housing. The greatest need is for large rental apartments. Two-family houses save money for owners and renters alike. It's time to make them legal.

Ben Ross was president of the Action Committee for Transit for 15 years. His book about the politics of urbanism and transit, Dead End: Suburban Sprawl and the Rebirth of American Urbanism, is now available in paperback. 


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You have to be joking. These regulations are insane. It's like we're wishing for average families to foreclose by forcing them to over-house. Why do we go on this way, even when we know our current living arrangements are unaffordable in this "new normal"?

by Phil LaCombe on Jul 31, 2012 3:01 pm • linkreport

Personally, I like the thrill of never knowing if I'm going to be suddenly evicted because my neighbor has a career change. And lawns are overrated, I should park my car on a paved over portion rather than the curb which could make the road narrower forcing people to slow down to the speed limit in my neighborhood.

by drumz on Jul 31, 2012 3:12 pm • linkreport

The proposed changes to accessory apartments as well as the current process to have an accessory apartment approved are both way too restrictive, infringe upon the rights of homeowners, and take away choice from rental residents.

Having an approved accessory apartment has to add value to the taxable assessment so Montgomery County is losing out on at least some property tax income at a time when every dollar counts.

by Scott Goldberg on Jul 31, 2012 3:15 pm • linkreport

@Scott G.
The taxable assessment is something I hadn't given much thought before. Obviously the assessment goes up if you construct a new accessory apartment, but how about if you subdivide an existing house into two units? It means at least the value of a new kitchen, right? That could add up over thousands of properties.

by Phil LaCombe on Jul 31, 2012 3:21 pm • linkreport

It's not like they are saying renting out part of your house to a roommate is illegal, they are just placing restrictions on full blown second units that function as if they were built like a duplex. When properties are developed in Montgomery County, there are a number of tests that must be passed as to school adequacy, utility and infrastructure adequacy and transportation adequacy. These homes were approved as one unit, with the assumed 2.6 person household and 2 cars. By making accessory apartments, you're changing that house into a duplex, which would generate more like 3.5 people per "roof" and adds a 3rd car. Seems trivial if it's just one or two, but if you start getting thousands of these types of conversions, it could quickly become a transportation and parking problem. Especially if we consider many single family detached neighborhoods are not served well by transit, and are often not in a grid street community. Maybe the answer would be to make it easier in certain locations (say a transit proximity overlay) but leave it more difficult in more suburban and remote locations.

by Gull on Jul 31, 2012 3:26 pm • linkreport

Ben: Can you elaborate on the staff and your thinking on possibly exempting from all of these restrictions flats being built for the purpose of taking care of disabled or aging family members who still could use the independence of having their own unit? I know that many jurisdictions give automatic variances to street setback rules for the purpose of handicap ramps.

by JimT on Jul 31, 2012 3:44 pm • linkreport

Even though I think these rules are nuts (except that a 2nd egress be created-I think that's reasonable) in all but one of them I can see the reasoning behind it, even if I disagree with it. The exception is the prohibition to putting the 2nd egress on the front of the house. I cannot fathom the logic to this except as occurring in a bigoted mind. Renters should not be seen entering/exiting their homes from the street? They must be hidden from public view? What is the reasoning behind this rule?

by Tina on Jul 31, 2012 3:52 pm • linkreport

--the rule that the owner must occupy the larger of the two units is based on a logic that is unfathomable to me too---

by Tina on Jul 31, 2012 3:56 pm • linkreport

"It's not like they are saying renting out part of your house to a roommate is illegal, they are just placing restrictions on full blown second units that function as if they were built like a duplex."

Really? It seems like having a renter in a room creates almost all of the same problems these rules are trying to prevent.

by Adam L on Jul 31, 2012 4:04 pm • linkreport

When people have lost 40% of their assets because of the burst of the housing value bubble, it's selfish and crass to make it impossible to make up for that loss by creating an accessory apartment.

Here in Bethesda I'm sure a lot of folks - especially older residents - would love to have some medical personnel from Bethesda Naval living downstairs.

by Capt. Hilts on Jul 31, 2012 4:22 pm • linkreport


Families are allowed to have lots of kids and/or own multiple cars.

If you want to regulate those things, do it directly. Don't do it by imposing arbitrary regulations on folks at the bottom end of the income ladder.

by andrew on Jul 31, 2012 4:27 pm • linkreport

@Adam L
you are correct that that having additional roommates would add to the population and thus all of the facilities I mention, but by code you've not created a second dwelling unit, which i'd imagine would likely lead to a larger increase in population density than just having people taking on a renter inside the existing dwelling.

the key is family. Why would a family live in two different dwellings. No one is regulating the actual family unit, they are regulating the non-family unit. I would assume you also have issue at the commonplace laws that prohibit more than 2, 3 or 4 unrelated adults from living in the same dwelling (depending on the jurisdiction)? The AVERAGE dwelling has 2.6 people, some have 5, others have 1. Likewise, many accessory apartments will have just 1 renter, but you may have up to the maximum number the code allows living there.

For the record i'm not against accessory apartments, but I do believe there needs to be a process to approving them, and i'm not sure the proposed regulations (other than the distance limitation) are really going to be that restrictive. I'd suggest the property owner seeking an accessory apartment could also be required to make the same adequate public facility payments that developers have to pay when building a new unit, but that's not even being proposed here.

by Gull on Jul 31, 2012 4:45 pm • linkreport

Andrew, you made a good point. Montgomery doesn't regulate family size or the number of cars they may own if they live in one dwelling.

So, it's okay for a family of eight with five cars to live in one house but not for a family of two with one or two renting the basement?

by Capt. Hilts on Jul 31, 2012 4:52 pm • linkreport

@Gull: No one is regulating the actual family unit, they are regulating the non-family unit.

Why is it okay to regulate non-family units, but not okay to represent family units?

by Gray on Jul 31, 2012 4:52 pm • linkreport

Er...regulate, not represent. I should have used the preview!

by Gray on Jul 31, 2012 4:53 pm • linkreport

While I haven't paid super close attention to this MoCo zoning proposal, I have been struck by the relative arbitrariness of the proposal. I don't think you mentioned the 2000 unit maximum number of allowable ADUs in the MoCo proposal.

By comparison, my upper northwest DC neighborhood is capable of absorbing hundreds and hundreds of such units (my block itself could probably absorb 30 or so). And that's just one couple square mile area.

That said, Gull makes two excellent points, both in terms of the general impact on civic infrastructure from adding population and that the proposal should be better targeted spatially, to be more focused on adding units in areas well served by transit.

E.g., while my neighborhood is super car oriented (it is on the outskirts of the city), a goodly portion of my neighborhood lies within a 1 mile walking-biking distance to Takoma Metro so the increase in cars that could result from mass construction of ADUs can be controlled.

And of course, in the core of the city, with high quality frequent transit service, the majority of ADU dwellers can be served by transit, walking, and biking rather than "having" to own cars.

by Richard Layman on Jul 31, 2012 5:09 pm • linkreport

@Gull ...they are regulating the non-family unit...
What do you mean? if a family rents out the unit then its a family occupied unit that is excessively regulated, i.e. can't be >800sq.ft; must be smaller than the owners unit (even if owner is a 75 yr old widow who lives by herself and doesn't need 800 sq ft for herself, but would value having a family of 4 in her house while she occupies a 1 bdrm apt..); must not see people entering or exiting the unit by the front of the house...

I agree w/@andrew re. the planning. Individual families can have many children and multiple generations, and extended family members all living under one roof, all with cars etc. and none of that is regulated. But granny can't create an apartment and rent the rest of the house to a family of 4?

by Tina on Jul 31, 2012 5:10 pm • linkreport

I'd like to hear other comments on this but my thought has been that this initial legislation is the "wedge" and it can be widened in the future. That is, it is MUCH harder to legalize something than it is to relax a law. So, in this view, the major battle has been "won" - accessory units are now allowed. In 3-5 years (or 10? Legislation can move really slow!), people can say "Look, there haven't been any problems - let's relax the law a bit." A much easier battle to fight.

by Wedgie on Jul 31, 2012 5:17 pm • linkreport

Related issue which I hope GGW tackles are the FHA rules on condo and rentals.

by charlie on Jul 31, 2012 5:20 pm • linkreport

I would assume you also have issue at the commonplace laws that prohibit more than 2, 3 or 4 unrelated adults from living in the same dwelling (depending on the jurisdiction)?

Yep, I sure do. Codifying the traditional family structure into random parts of the building/housing code is problematic in more ways than I can possibly even begin to enumerate. (Also, those regs aren't as common as you think they are.)

People come from many different molds, and regulations like this create an unacceptably-high number of "edge-cases," where the intent of the law is unfairly or unevenly applied.

Does the government have a legitimate interest in maintaining the average number of inhabitants per dwelling at 2.6? If you are concerned about population growth, revenue collection, sanitary conditions, or parking, there are practicable individual solutions to each of those problems that will not unintentionally alienate segments of the population.

by andrew on Jul 31, 2012 5:40 pm • linkreport

The regs are ridiculous and actually seem to encourage small, easily abused spaces. A better fix would be to approve construction of two family houses---these were one of the vernacular house styles in some places until the middle 20th century and can be designed to look more or less like single family homes.

by Rich on Jul 31, 2012 6:13 pm • linkreport

Montgomery County doesn't want affordable housing. We've worked hard not to live down the street from poor people.

by Neutrino on Jul 31, 2012 7:39 pm • linkreport


Montgomery County already allows homeowners to build an apartment within their home by right if it's for a family member. They're called Registered Living Units, and there are about 500 of them in the county today. You can allow family members to live in them for as long as you want, but if you want to rent them out, you'll have to go through the approval process, including a public hearing.

As I wrote last month, the existing approval process for accessory apartments is so onerous that it forces many homeowners to build illegal units.

The proposed policy isn't much better, as the proximity requirement makes it harder to build accessory units in the places where they'd most be helpful: in downcounty neighborhoods that are already well-served by transit and have amenities within walking distance, meaning that tenants won't need a car (or need to drive as much). If you share the concerns Ben and I have raised, you should make yourself heard at the County Council's public hearing on the proposed regulations on September 11.

by dan reed! on Jul 31, 2012 10:25 pm • linkreport

@Ben Ross: I think your reading of the maximum sq.ft. of an accessory apartment in the proposed zoning regs is a bit off. There are two categories of both attached and detached accessory apartments, small and large. For both, the accessory apartment cannot be more than either 800sf or 1,200sf (respectively) or 50% of the floor area of the principle residence. So if you have a house that has 1,200sf on both the main level and a second level, you can have up to a 1,200sf basement accessory apartment.

by IsoTopor on Aug 1, 2012 12:32 am • linkreport

@Ben Ross:

Where in the regs does it say the owner must live in the larger of the two units? I'm not seeing it.

And why are we calling it two-unit living? The additional unit is called an accessory apartment, and they can be either attached or detached like IsoTopor. This is different from a duplex.

C'mon, GGW.

by Wheatonite on Aug 1, 2012 9:23 am • linkreport

instead of addressing each individual comment i'll make a final blanket statement.

The people that seem to be on the attack and hate these regulations seem to forget that these are being applied to established single family detached neighborhoods that were a - not designed to add this new capacity and b - are likely full of homeowners who purchased their property thinking they were purchasing in a single family detached neighborhood.

It also goes beyond just looking at household size (although that is still a major argument for regulating the number of these units allowed). There is also the mental barrier people are going to have about renters. Most people who rent are great people, I myself rent, and I myself would love an accessory apartment. But i'm also aware that there is a stigma attached to renters, and as another comment suggested, the biggest hurdle is going to be getting any law in place that recognizes these units. Their has been a lot of public outcry over this legislation from people who do not want it at all. Adopting a limited version of this legislation may be the smartest way to show the group of nay-sayers that this will not be the detriment of their community. Imposing a new development pattern on them without their cooperation is just as offensive as you feel the County is being toward you by making these types of dwellings difficult to come by.

Also, most people who are looking for these accessory apartments are likely to be younger professionals, or elderly, and are going to be single or at least a couple without children. The same demographic that we already find is driving the resurgence of urbanization in this Country. Most are going to want to be transit accessible, and are not even going to be interested in living in 70% of MoCo's housing stock. The better idea in my opinion is to have more restrictive rules on accessory apartments in the more "suburban" or "rural" areas of the County, and more relaxed rules closer to the concentration of transit opportunities (and jobs).

I do not think most of these regulations are going to have a huge limiting factor on accessory apartments - just because the door has to open to the side (it's not to hide the renters, it's to make the house still look like a single family detached unit from the street), or because the larger of the two units has to be lived in by the owner (this is an accessory apartment rule, not a 'convert single family dwelling into duplex' rule). The only real limit is the rule limiting how close the next accessory unit can be located. Honestly, building these units takes time and money and even if there were very relaxed regulations you're not going to see thousands of these units appearing tomorrow. I support getting the language in the code, and starting with heavy regulation until all sides involved have a handle on how this will work.

by Gull on Aug 1, 2012 9:24 am • linkreport

I suggest this essay by Chuck Marohn, "Residential Maturing"

by Phil LaCombe on Aug 1, 2012 9:31 am • linkreport

What's missing from this discussion, as usual, is the issue of school capacity. Montgomery County Public Schools are already educating over 10,000 public school students in overseas containers outside of school buildings. Until we can figure out how to plan for growth that includes where public school children will go to school, this conversation is absurd. More housing = more public school students. It just does. People have babies. Babies have a right to a free public education in the state of Maryland. More housing = more classrooms and more school buses. That's the reality. Real planners would be looking at the big picture.

by Janis on Aug 2, 2012 2:18 pm • linkreport

@Janis -- What's missing from this discussion, as usual, is the issue of school capacity.

Given that the proposed requirements limit an accessory apartment to no more than 3 people, I don't think that we should panic that an occasional apartment will bring a serious influx of new children to a school. A new housing development might do that, especially if made of single-family homes. But an occasional accessory apartment --- I don't think so.

by Tina Slater on Aug 5, 2012 11:01 am • linkreport

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