The raised floor has been the default for decades. But the industry is moving on.
Most data centers were built around the same basic premise: raise the floor, run cables underneath, push cold air up through perforated tiles. It worked. For a long time, it was plenty. But as rack densities climb and sustainability pressures mount, that legacy approach is being weighed against something simpler, cheaper, and more efficient.
More and more data centers, from hyperscale giants to smaller enterprise deployments, are switching to slab floors, flooding the room with cold supply air, and relying on hot aisle containment (HAC) to push exhaust back through a plenum ceiling return. The result is a design that’s easier to scale, easier to maintain, and built to wring every possible efficiency gain out of the cooling system.
This white paper walks through exactly why that shift is happening, and what it takes to do it right.
What’s Covered Inside
Raised Floor vs. Slab Floor
A clear-eyed look at both designs: where raised floors still earn their place (colocation facilities, low-density racks, high-change environments) and where slab floors win on cost, flexibility, seismic performance, and efficiency.
Containment Options
A look at how Subzero Engineering’s AisleFrame system provides hot aisle containment, infrastructure support, and rapid deployment in one ground-supported structure, with approximately 2% leakage.
Maximizing Energy Efficiency and Sustainability
How to match supply airflow to demand airflow, minimize bypass losses, raise cooling set points toward ASHRAE limits, and build a data center that uses only the energy it needs.
Slab Floors and Simplified Cooling
Why flooding the data center with cold supply air, rather than routing it through overhead ducts and diffusers, produces a more manageable and higher-performing environment.
Plenum Ceiling Options
Contributed by Bill Frantz of Armstrong World Industries, this section examines how ceiling systems are often the overlooked weak link. A standard non-gasketed ceiling can leak at 1.44 cfm/ft2. Armstrong’s Ultima AirAssure tiles with DynaMax structural grid bring that down to 0.19 cfm/ft2, on par with the rest of the containment system.
CURRENT INDUSTRY QUESTIONS
This white paper will answer
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When does a raised floor still make sense, and when should you move on? -
How does flooding a room with cold supply air actually improve cooling performance? -
Why does ceiling leakage matter as much as containment leakage? -
What does a low-leakage plenum ceiling system contribute to energy savings? -
How do containment and ceiling work together to hit maximum efficiency?