After nearly a decade of in-row and overhead cooling dominating data center design, underfloor air distribution is experiencing a significant resurgence driven by AI computing demands. Raised floor plenum delivery places cooled air directly adjacent to server intake points, reducing the distance conditioned air must travel and minimizing thermal losses from mixing with ambient room air. This proximity advantage translates to supply air temperature reductions of two to four degrees Celsius compared to overhead systems delivering the same cooling capacity, with corresponding energy savings of fifteen to twenty-five percent in fan power consumption that directly improve the facility’s power usage effectiveness.
The best raised floor for data center UFAD configurations requires specific design considerations including perforated panel placement aligned with cold aisle configurations and underfloor plenum depth that accommodates airflow velocities without turbulent pressure losses. Modern computational fluid dynamics modeling allows designers to optimize these parameters achieving temperature uniformity within plus or minus one degree Celsius across entire cold aisle arrays. The calcium sulfate raised access floor panels offer particular advantages for UFAD applications because their dense non-porous core material resists moisture absorption in the high-humidity environment of a cooling plenum, maintaining structural properties that alternative core materials may lose over time when exposed to continuous moisture. Global data center trends in 2026 indicate that UFAD with containment is the fastest-growing cooling configuration for new hyperscale facilities.
PUE Improvement With UFAD Systems
The PUE improvement potential of UFAD systems is substantial. Comprehensive studies of retrofitted data centers show that switching from perimeter computer room air handlers with overhead supply to raised floor UFAD with containment reduces PUE by an average of 0.15 to 0.25. For a ten-megawatt facility operating at an electricity cost of ten cents per kilowatt-hour, this PUE improvement translates to annual energy savings of one hundred thirty thousand to two hundred twenty thousand dollars. The payback period for the UFAD system upgrade including the raised floor installation is typically eighteen to thirty months, making it one of the most cost-effective energy efficiency investments available for existing data center facilities that currently operate with less efficient cooling configurations.
Projections indicate UFAD will account for more than forty percent of new data center cooling installations by 2028. This growth is supported by improvements in gasket sealing systems, more precise perforated panel airflow control through adjustable damper mechanisms, and integrated underfloor leak detection that addresses historical concerns about water damage from cooling equipment located below the raised floor. For data center designers evaluating cooling strategies alongside the evolving data center infrastructure trends, the UFAD return combines proven plenum delivery simplicity with modern control systems that optimize airflow in real time based on temperature sensor feedback from each cold aisle.
For data center designers evaluating UFAD implementation, the most important early design decision is the underfloor plenum depth, which must accommodate both the airflow volume requirements and the space needed for cable routing and other underfloor services. A minimum plenum depth of three hundred millimeters is recommended for most applications, with deeper plenums of four hundred to six hundred millimeters preferred for facilities with high airflow requirements or complex cable distribution needs. The plenum depth directly affects the building floor-to-floor height and total building cost, so optimizing this dimension early in the design process avoids costly structural modifications later. Computational fluid dynamics modeling during the design phase allows the project team to verify that the selected plenum depth and perforated panel layout will achieve the required cooling performance before construction begins, eliminating the risk of thermal issues discovered during commissioning that would be expensive to correct after the raised floor is installed.