The building is clad with white glazed brick and field limestone, which matches the original slate-clad mansard roof of the existing library.
The structural system includes structural steel beams and columns; plywood-sheathed, cold-formed metal stud shear walls; a composite concrete slab and steel beam floor system; and cast-in-place concrete basement walls. Another striking feature of the addition is the one-story Memorial Walk along the north side of the existing building. This steel-framed, glass-clad addition provides views of the restored Memorial Garden and direct access to the Night Watch Gallery, which houses the historic “Night Watch” oil painting.