Case Study: National Institutes Of Health

Fireloops® Cross Building’s Expansion Joints To Protect Fire Sprinkler System

“The installation was easy,” commented Keith Cunningham, Foreman, National Fire Protection, Inc. “It was the first time we had installed a joint to handle building movement, as well as the first time to install loops, and these went in real easy.”

Expansion joints not part of original design

Mark O. Hatfield Clinical Research Center is a 850,000 square foot addition to the National Institutes of Health (NIH) Clinical Center. It will be a highly efficient and flexible state-of-the-art facility with 600,000 square feet of hospital and 250,000 square feet of research laboratories.

The need for joints that crossed over the building’s expansion joint came in as a change order.

The joints needed to fit into the existing design, and allow for the building movements specified in the revised plans.


The Metraflex FireLoop®  was specified in 2-inch, 2-1/2 inch and 3-inch sizes with grooved ends. The loops were installed in 30 locations in mains and branch lines throughout the fire protection system and pressurized to 175 psi.

Thirty FireLoop expansion loops, installed parallel to the ceiling, were placed at the building’s separation joint in mains and branch lines throughout the building.

“We installed the Fireloops parallel to the ceiling and all we needed were hangers for the end, and at the two connections,” Keith explained.

Having never installed loops before, Keith was pleased with the simplicity of the installation. “I would use the Fireloops again in other projects in the future,” he commented.

Learn More About the FireLoop®