Investigation of the Integration of Interstitial Building Spaces on Costs and Time of Facility Maintenance for U.S. Army Hospitals

The U.S. Army Medical Department (AMEDD) has used the interstitial building system (IBS) as a design component for some of the hospitals in its healthcare infrastructure portfolio. Department of Defense (DoD) leadership is aware of increases in healthcare costs and understands the importance of safely reducing costs, which may be possible through design initiatives. An analysis was performed on facility maintenance metrics for ten different U.S. Army hospitals, including IBS design and conventional / non-interstitial building system (NIBS) design.

Statistical analysis indicated a significant difference in cost and time data between IBS and NIBS for most of the building systems considered (HVAC, electrical, plumbing, and interior). Scheduled maintenance for the plumbing building system was not found to have a significant difference in costs; scheduled maintenance for the HVAC and plumbing building system was not found to have a significant difference in time expended. The data in this study showed that facility maintenance cost and time were generally lower for IBS than NIBS. Time spent (and associated cost) for scheduled maintenance of the electrical and plumbing building systems were slightly higher in IBS, though not significantly higher for plumbing. It may be easier to reach the plumbing and electrical building systems due to the greater accessibility afforded by IBS design.

While a cost premium is estimated for integrating IBS design, the savings provided by life cycle facility maintenance is estimated to be up to three and a half times the initial cost premium.