See this news from the DC Historic Preservation Office:
HRPB ACTIONS for May 28 and June 4, 2015
Chapman Coal Company Stable and Garage, 57 N Street, NW, HPA 15-306, subdivision, concept/addition, alteration, new construction.
The Board approved the subdivision of the property to include a consolidation of Lots 214 and 215 on Square 0617, and it approved the concept/addition, alteration and new construction of the property with the following conditions: (1) The roof addition on the landmark be set back so as to be minimally visible from N Street, or removed entirely; (2) The hyphen connecting the landmark and the new construction should be reduced in height; (3) the iron stair and canopy should be repaired and retained; and (4) a building preservation plan, to include specifications for replacement windows based upon historic existing ones should be prepared. Vote: 8-0.