A partially-occupied twelve story building at the intersection of 14th Street and New York Avenue in downtown Washington DC, proved to be a uniquely challenging renovation for Hardesty Concrete. Substantial off-hour and weekend work was required to minimize the disruption to tenants. A structural slab extension was added on numerous floors to accommodate a new glass façade. Additional work was also done on the interior of the building, infilling existing slab openings that were no longer needed. Uniform slab elevations were achieved by installing lightweight concrete and insulation at slabs and stairs.