When a Duplex Isn’t a Duplex

A bill sponsored by at-large council member Charlie Tygard, scheduled for third and final reading Tuesday, would modify this definition to include the following: “two detached dwelling units separated by at least 10 feet, provided that the distance can be less than 10 feet if the facing walls on both units are rated according to the Standard Building Code as adopted by the Metropolitan Government pursuant to Chapter 16.08 of the Metropolitan Code of Laws.” Got it?

If not, let’s try layman’s terms. On those lots in Metro Nashville zoned to permit two-family, the current code allows two houses if they are attached by an 8-foot cube. The result has been what can only charitably be characterized as an architectural oddity: pairs of two-story houses linked by a short squat hyphen. In Green Hills, where this oddity is most prevalent, the hyphen is often carefully screened by landscaping and frequently used as a storage shed.

If Tygard’s bill is adopted, the hyphen could be omitted. Thus two single family houses on the same lot would qualify as two-family if they are 10 feet apart, or less if the facing walls pass certain fire ratings. We’ve come a long way from the traditional duplex.

We got to this point due to imprecision in the comprehensive zoning code of 1974, compounded by a misguided attempt to be more exact. According to Metro zoning administrator Sonny West, the original code defined duplex as “two dwelling units in any way connected or joined by their construction.” When this code was revised in the 1990s, West says, “we wanted to give some minimum dimensions to the connection, to make some usable space, so that somebody couldn’t just join two units with a 3-foot breezeway.” Hence the 8-foot cube.

Mandy Wachtler, president of the Greater Nashville Association of Realtors, says real estate agents support the cleavage between what the industry quaintly calls “horizontal regimes.” “We don’t even use the words ‘two-family,’ ” Wachtler says, presumably because of the “rental” connotations. “Omitting the connector would make each unit more salable. Normally for new construction, people don’t want to touch when it’s two units. And why make them touch because of an antiquated code?” She notes that the 8-foot connector cube “puts some wrinkles into design [and] can create some odd placements.” She also notes that in pricey areas like Green Hills, “a single family on a single lot sells for over a million because of the cost of the land. Two on a lot is a way to get new construction for less than a million because you divide the land cost.”

Sponsor Tygard points out that splitting apart the units won’t mean the subdivision of lots, because the lot would remain intact as the common property of the two units, along the lines of condo developments. And he says that his new definition wouldn’t change any other current rules that apply to two-family construction. “The maximum building coverage [of a lot], the maximum height and the required setbacks would stay the same. And you’re not increasing density, because you could only build two [detached] units on a lot that’s already zoned for two-family. Most of Green Hills has already been down-zoned to single family.”

These reassurances failed to assuage some residents of traditional urban neighborhoods, such as East Nashville and Belmont-Hillsboro, who are concerned that eliminating the required connector would deliver a flood of garage apartments. West counters that this scenario is unlikely because of the relatively small lots in these neighborhoods. “A pure garage requires a 5-foot setback. One with a dwelling above requires a 20-foot rear setback,” he explains. “So a garage on an alley won’t qualify.”

In a letter to members of the Metro Council, the Nashville Neighborhood Defense Fund (NNDF) objects that “this change will increase the number of tear-downs in existing neighborhoods.” The logic is that if the ugly connector is eliminated, and if buyers prefer even barely detached dwellings anyway, developers will scrape more lots to build this more desirable product. NNDF also fears that, “In time it is likely that owners will request sub-division of these lots creating a confusing patchwork of sub-standard lots through existing neighborhoods.”

In response, Tygard amended his bill to eliminate from the new duplex definition the urban neighborhoods—those that fall within the pre-Metro city limits of Nashville (essentially the area inscribed by I-440 covered by what’s called the urban zoning overlay)—as well as those properties covered by historic preservation overlays. “All I was trying to do was get rid of the stupid connector you see in Green Hills,” he explains, almost plaintively.