Jordan and Skala Engineers Inc.: VA San Juan Medical Center – Outpatient Addition

Addition to existing building at a hospital/health care facility.

By Jordan & Skala Engineers Inc. August 14, 2014

Engineering firm: Jordan & Skala Engineers Inc.
2014 MEP Giants rank: 45
Project: VA San Juan Medical Center – Outpatient Addition
Address: San Juan, Puerto Rico, U.S.
Building type: Hospital/health care facility
Project type: Addition to existing building
Engineering services: HVAC/mechanical, energy/sustainability, and plumbing/piping
Project timeline: 1/1/2013 to 6/19/2014
MEP/FP budget: $700,000


The project was to add a new second floor to an existing single-level ambulatory care facility. New HVAC systems included multiple constant and variable volume air systems with high levels of filtration, new fans, and new air handling units. There were two major design challenges: First, the existing facility had to remain in operation during construction. Second, all 30 of the existing air handling units as well as the building exhaust fans, the vent fume hoods, and the cooling towers were located on the existing roof. Together the existing equipment occupied approximately 65% of the worksite surface area.


The work was completed in a detailed phasing plan, which took nearly 5 years to develop. Systems and installation procedures were all designed to minimize shutdown. To keep the existing building systems in operation while adding the second floor, two critical components had to be constructed: an intermediary floor above the existing roof, and a mechanical penthouse. Within the newly created interstitial space, the ductwork to the existing equipment was reconfigured to align to the placement of the future equipment on the new penthouse. Structurally, the new second-floor slab and roof were built around the existing equipment to allow for future connection. Needless to say, this created a job site with extreme fall protection concerns. The 15 units that replaced the existing units were situated on the penthouse. The ductwork for the new units was installed to align with the existing units. In an 8-hour window, the old unit was taken off-line, the ductwork was made contiguous, the old roof was removed under the unit, the void in the new slab was formed and poured with concrete, and the roof was completed. Within the project there were 15 8-hour, overnight critical installation events. Later in the project the team installed an additional 15 units on the penthouse to support the square footage added to the building by the new story. In addition to the rooftop unit installation, plans required the size of the existing chiller plant to more than double, to nearly 30×10-ft, and to be relocated to a side canopy. The original cooling towers located on the original roof remained in service until the new cooling towers and piping were put in service on the second-floor roof.