This massive federal building sits at the corner of Cadman Plaza East and Tillary Street in downtown Brooklyn. The project consisted of historic replication of existing sash and the restoration of existing sash. Each sash was retrofitted to accept insulated glass units. The weatherstripping system was changed and the necessary Dutchmen and epoxy repairs were made on the sash and frames. These changes provided the client (the GSA) with a window system that was usable, efficient, and durable.