Brooklyn’s PS 77 is a 68,000 SF historic school built in 1896 (with several additions since then) that was in desperate need of repairs. DRG Architects with our consultants conducted a thorough field survey and extensive forensic testing to evaluate PS 77’s exterior envelope (structure, masonry, roofing, parapets, windows, and doors) and source of courtyard flooding. Water spray testing and structural probes revealed that all five components of the exterior envelope will have to be addressed in order to resolve the water ingress issues. Since extensive reconstruction of the exterior masonry was part of the design solution accurate drawings of the building are critical. DRG Architect’s scoping team researched the school’s history and was able to locate the original building drawings with the Brooklyn Building Dept. and the Brooklyn Arch Diocese. The team also solicited bids to have a 3-D laser scan of the building performed, so that accurate drawings could be created. DRG Architects developed a pre-design assessment report which defined the scope, approach, budget, and schedule for the project. The project scope included building envelope upgrade project that incorporated a full face brick replacement was designed to allow for a new cavity wall system to be installed thus eliminating water infiltration from the masonry; new walls and ceilings replaced the plaster containing asbestos walls and ceilings; existing wood windows and steel windows were replaced with increased thermal-efficient aluminum windows which also eliminated water and air infiltration.
The existing roof structure was arched terracotta, which was determined by the pre-design assessment that it was not structurally sound and needed to be replaced. The roof was demolished and replaced with a steel frame metal deck with a concrete roof. The original roofing contained asbestos which was removed prior to demolition; detailed architectural cast stones and copings were replaced with matching cast stones. Finally, a new four-pipe hydronic heating and cooling system with room unit ventilators connected to a new mechanical room at basement level and new pump room and chiller on the roof. Intrusion and surveillance security systems were also added, old plumbing fixtures replaced, electrical panels updated, and 35 percent of lighting fixtures replaced with new energy-efficient/long-life LED lighting. The new building envelope will achieve all design/upgrade goals to improve the indoor air quality of the interior spaces, increase energy efficiency, and prevent water penetration. The project required submissions and approvals from various NY and NYC agencies, including working closely with the State Historic Preservation Office (SHPO).