A warm but spare 950-square-foot apartment blends the best of old and new disposing of, salvaging, adding and combining material elements to bring out the authentic patina of this 2010 triple-decker.  Within the space existing wood doors and hardware were recommissioned, structural wood wall studs uncovered to form a screen wall, and existing cast iron radiators painted gold.  Using DC tax incentives and basic technologies energy use is minimized.  New insulation, a high-efficiency mechanical system, windows, a new bath with dual flush toilets, new light fixtures and solar roof panels help minimize energy needs and modernize the space.