Myth: The Zoning Update will allow residents to build McMansions or apartment buildings in their back yards.
Fact: We’re proposing some modest changes to the rules for accessory dwelling units (or ADUs). ADUs are actually already allowed under the current zoning regulations (we now call them “accessory apartments,” but “accessory dwelling unit” is the more common term throughout the U.S.).
Under the zoning regulations in place today, residents in R-1, R-2, and R-3 zones can have an ADU within their home, but they are required to obtain a special exception from the BZA. There are a host of other rules that apply: the ADU can be no larger than 25% of the house, the owner must occupy either the main dwelling unit or the ADU, and so on.
Interestingly, homeowners in R-1 can also have an ADU above their garage by-right, under the current rules. There are very few restrictions governing these ADUs—the building can measure 20 feet in height and, as long as the main building and the garage stay within the lot occupancy restrictions of the zone, there are no limits on the size of the ADU. There is one restriction; the ADU must be for a “domestic employee.” While this rule might have made sense in an era where live-in housekeepers were common (at least for a certain part of the population), we’re not sure it applies to many families today.
So, as we engaged in our comprehensive review of the zoning regulations, a couple of things struck us as odd.
First, the current regulations treat an ADU within your home much more restrictively than one in a separate building. Remember, as long as you can show some evidence that your tenant is a “domestic employee,” you’re allowed to add an apartment on to that garage without any public review of how big it is, or what impacts it might have. In contrast, ADUs inside the home, which are comparatively small and hidden from view, must go through a public hearing.
Second, for our R-1 zones, there’s nothing that says you can’t have both the ADU within your house and the one over your garage. In theory, you could have three independent dwelling units on the same property. (Granted, we’re not aware of anyone taking advantage of this.)
At the same time, we expect much more interest in this type of living arrangement in the future. A recent Washington Post article showed how families in Virginia are using ADUs as a way to provide independent living for aging parents. It’s also a way for young homeowners to get some additional income to help with the mortgage, or to offer more choices to the greater number of small households arriving in the District every day.
So, here’s what we’ve proposed:
- If you want an ADU inside your house, you would be able to do it by-right (provided you follow all the rules limiting its size, maintain owner-occupancy, etc.).
- If you want an ADU in an existing garage or carriage house (the catch-all term we use is “accessory building”), you could also do it by right. Again, there are some restrictions; see below.
- If you want to build a new ADU in your backyard, you’d have to get a special exception; we’d also require a special exception if you were going to put an ADU in a garage or carriage house that was expanded after the new regulations went into effect.
So, could you build a monster home in your backyard? Not really. Remember, the only way to add an ADU in an existing accessory building is to not enlarge the structure – the accessory building would have to remain its current size. We think this makes perfect sense in older neighborhoods, where many homeowners have carriage houses that can’t be readily adapted for other uses. We see ADUs as great spaces for young residents looking for affordable housing options or elderly residents that want to be close to their families so they can help raise their grandchildren.
If you’re building something new (or adding on to an existing accessory building), here’s what you’d have to do, in addition to seeking a special exception, which includes a public hearing so neighbors can voice any concerns:
- Keep the footprint of the building to 450 square feet or less.
- Keep all balconies or decks within that footprint, and make sure they don’t face the immediately adjoining houses (currently, those balconies and decks are unregulated).
- Keep the total living area to 900 square feet or less (in other words, you could have two full stories).
- Keep the height of the building to no more than 22 feet (remember, you can do 20 feet now for your “domestic employee” apartment; we’re proposing an extra two feet to account for the slope of a roof).
- Stay at least 30 feet away from the main building (we want an adequate distance for light, air, open space, and fire separation).
- Keep any other accessory uses out of an accessory building with an ADU in it, except for a garage (we’re assuming this is independent living space, not an opportunity for the homeowner to expand a home business, but we thought it best to be clear).
If it sounds like we’re being a little detail-oriented here, that’s because we want to be sure that any new construction fits into the fabric of single-family neighborhoods. And it’s possible that, without some oversight, the greater interest we anticipate could lead to some unintended consequences. That’s why we’re closing loopholes, setting some reasonable limits, and giving neighbors an opportunity to weigh in on the most significant changes or additions.
Would you want an ADU on your property? How about your neighbor’s? And what rules should we expect people to follow if they want to build one?