DC’s Historic Preservation Review Board approved a roof deck for a row house near 15th and T last month, but not before a few members lamented ever setting a precedent of allowing them in the first place.

Left: The rear of the house on T Street requesting a deck. Right: A less attractive deck across the alley. Photos from the DC Historic Preservation Office.

In the Dupont, Logan, and U Street historic districts, many alleys have a wide variety of decks on the backs and tops of row houses. The practice for many years has been to deny additions to row houses which are visible from in front of the house, but to be much more permissive about changes on the alley side.

Following that precedent, Historic Preservation Office staff reviewer Kim Elliott recommended the board approve the deck.

However, Elliott also noted that unlike on some blocks, all of the 2-story row houses here have the same, uninterrupted roof line from the back (as well as the front). The 3-foot high railing for this deck would create a pop-up effect from the rear. Elliott pointed out that the board started allowing roof decks some years ago, setting a precedent.

The Historic Preservation Review Board ultimately agreed with Elliott and approved the deck, though Bob Sonderman suggested making the owner shrink the deck a few more feet by pushing the railing back away from the rear of the house.

Members Graham Davidson, an architect at Hartman-Cox, and Nancy Metzger, formerly with the Capitol Hill Restoration Society, both wondered if the board might have made a mistake allowing roof decks in the first place. The pair have been fairly consistently the most skeptical of buildings and have pushed hardest for changes like removing floors from new buildings.

Here are the comments from Davidson and Metzger on this case during the board’s meeting:

Still allow decks, but insist on quality?

Davidson noted that many of these decks are fairly “poorly built” and “clunky,” because people are trying to get them done at low cost. He’d like to “improve the quality of alleys” throughout the city. That’s a worthy impulse, but why do many preservationists thus feel that the solution is to reject the decks or shrink them toward invisibility?

The preservation board also has power over the materials people use for additions, decks, and other projects. It can demand a higher quality of design and construction.

As with the pop-up across from Geoff Hatchard’s house in Trinidad, which he just wrote about, he doesn’t seem to object so much to the house getting a 3rd story as to the cheap vinyl siding design. In that case, we might wish a preservation board had the power, and willingness, to let the 3rd story go through but demand better quality.

The DC Comprehensive Plan calls for exploring “conservation districts,” a less restrictive form of historic preservation. Preservation can control, or not control, 2 categories of changes: where and how large to build, on the one hand, and its materials and quality, on the other.

Some might want a conservation district to be the equivalent of lower zoning, where the board gets to veto anything that builds up in any way, but it would make far more sense for such a district to permit additions that meet zoning rules, but ensure that their appearance be compatible with surrounding buildings.

Of course, “compatible” is always tricky to define, as is “higher quality.” Most neighbors would want an addition like the one on Geoff’s street to simply make the building look like it had always had 3 stories. But many preservationists think that any new construction should stand out from the old, and might push instead for something of modern appearance. This is a question the neighborhood should discuss if such a district came into being for Trinidad, and written guidelines should codify those choices.

Preservation, even a limited form, would potentially raise the cost of building. Certainly it might make the pop-up across from Geoff more expensive. In some neighborhoods, that can limit new supply and/or make new housing more costly. In an area like Trinidad today, though, prices are rising so fast that rules to push for higher quality would likely affect profit margins more than the growth of supply.

On T Street and other areas with historic protection, the city could indeed “improve the quality of alleys” as Davidson wishes. But let’s not define “higher quality” as “bereft of decks.” Instead, it can mean “filled with attractive decks that don’t look cheap.”

David Alpert is the founder of Greater Greater Washington and its board president. He worked as a Product Manager for Google for six years and has lived in the Boston, San Francisco, and New York metro areas in addition to Washington, DC. He lives with his wife and two children in Dupont Circle.