Duke University Chapel, Durham, N.C.
Retrofit Team
HVAC Cleaning and Service: Pur-Vent, Cary, N.C.
Materials
In May 2015, Duke University kicked off a year-long restoration project to rehabilitate the interior and exterior of the chapel. Pur-Vent was tasked with restoring the entire HVAC system, including 100 feet of underground ductwork.
Duke University was replacing the existing air-handling units, and Pur-Vent was responsible for cleaning all of the remaining ductwork and grilles. The project’s scope was eventually expanded to include 100 feet of underground fresh-air ducts that had previously been taken out of service. “They decided to put it back in service, and they wanted to coat it, so we suggested using Carlisle Hardcast’s RE-500,” says Henry Baker, president of Pur-Vent.
A building’s ductwork can be resurfaced—as opposed to being replaced—with RE-500, a high-performance, spray-applied insulation coating. Coating the fiberglass liner or duct board with RE-500 increases the equipment’s service life at a fraction of the cost of replacement. RE-500 is a low-VOC product that can be used inside the HVAC ductwork.
Pur-Vent’s technicians first cleaned the ductwork with vacuums; then they performed a more thorough cleaning using whips and air-washing. Duct cleaning is extremely important for a facility to have a healthy and efficient airflow system and, after cleaning, sealing and coating the duct system is essential to ensure that dirty, dusty air is not pulled into the ducts and recirculated throughout the building.
“Architects and engineers are starting to realize that you can’t just replace an air-handling unit and not clean the existing ductwork and the air distribution, especially if you put new ductwork downstream. I’ve seen cases where dirt from old ductwork blew into the new ductwork, then the entire duct system has to be cleaned,” Baker recalls.
Because the Duke University Chapel is such a significant building, Pur-Vent’s first priority was
to preserve its historic elements, including the brass grilles, limestone walls and woodwork. “The air distribution was literally on top of the woodwork and the entire back of the seats were the air plenum, so we had to go down in back of that and clean that out,” Baker explains. “Getting zoning and enough suction on that was tough.”
After the clean-up phase of the project was complete, Pur-Vent technicians hand-applied RE-500 using an airless sprayer.
Ductwork Resurfacing: Carlisle Hardcast’s RE-500 by Carlisle HVAC
The Retrofit
Since the early 1930s, Duke University Chapel has stood on the highest ridge of Duke’s West Campus. this iconic building has a rich history and is known for its architectural grandeur. During the past eight decades, Duke University Chapel has been the site of thousands of services, welcomed millions of guests and served as the preeminent icon for the distinguished university.
View a video of Duke University Chapel’s HVAC restoration.
PHOTOS: Carlisle HVAC