GC: Harkins Builders Scope of Work: Fluid Applied Air Barrier, Spray Foam Insulation & Wet Spray Cellulose Insulation The Shell, in the Columbia Heights West neighborhood, is a planned 83-unit affordable apartment building at the intersection of Columbia Pike and Greenbrier Street. The planned six-story structure will be built around a central courtyard with ground floor retail on Columbia Pike. The project will be EarthCraft certified and also feature a green roof.