Vertical Integration: Stacking Cleanroom Performance and Storage

To solve this problem, ICON Mechanical reached out to warehouse storage and material handling specialist Stein Service & Supply. Recognizing that a standard layout would not fit the physical constraints of the facility, John Mayo and the Stein team partnered with modular building expert Panel Built, Inc. Together, this collaborative team engineered a custom, two-story modular solution that stacked a fully loaded structural mezzanine directly on top of a cleanroom, doubling the utility of a single footprint.

Shifting the layout upward introduced an immediate engineering hurdle. ICON Mechanical requested a wide-open cleanroom floor with absolutely no internal columns to ensure unhindered material handling and total layout flexibility. At the same time, the ceiling of this cleanroom had to act as the floor of an elevated mezzanine capable of supporting heavy tools and parts storage. To deliver on this request, Panel Built's engineering team moved all structural support columns and wide-flange beams to the exterior perimeter. By meticulously designing the open web steel bar joist configuration beneath the upper deck, they successfully transferred the immense weight loads to the outer boundaries, keeping the cleanroom interior entirely clear.

The lower level of the installation is a 2,496 square foot cleanroom operating to strict ISO 8 standards, ensuring absolute environmental control. The structure was built using Panel Built's 3-inch, 3-ply insulated wall panels, featuring a vinyl-covered gypsum finish for simple cleaning and a solid polystyrene foam core for thermal stability. With a 10-foot ceiling height, the space integrates personnel doors, flush windows, and dedicated HEPA filtration units. For smooth logistics, the engineers framed a large 12-foot by 10-foot opening to accommodate a high-speed roll-up door. This asset lets the crew transfer heavy fabrication equipment and raw steel assemblies rapidly without disrupting the cleanroom's climate control.

Directly above, the structural mezzanine deck provides a spacious platform for tool organization and parts storage. Workers reach this upper level via bar grating steel stairs finished in high-visibility Performance Yellow, complete with closed risers and a diamond plate landing for safety. To prevent the strain of hauling heavy parts up a staircase, the layout incorporates an integrated vertical conveyor lift system, allowing smooth mechanical movement of equipment between levels. The upper deck uses 3/4-inch tongue-and-groove ResinDek LD engineered floor panels over a 20-gauge steel B-deck. Unlike standard plywood, ResinDek resists flaking and cracking, protecting the clean room below from particle contamination while easily handling heavy foot traffic and wheeled dollies.

The entire prefabricated system offered an incredibly fast path to completion. Though administrative permitting delays initially stretched the timeline, the physical installation on-site moved quickly once approvals cleared. The crew completely assembled the 2,496-square-foot structure in just six weeks, keeping construction dust and operational disruptions to an absolute minimum.

This modular approach also guarantees long-term flexibility. Because the mezzanine structure is entirely free-standing, it stands on its own columns without anchoring into existing factory walls or using building columns for support. If ICON Mechanical ever needs to reconfigure their Charlotte floorplan down the road, the entire system can be altered, expanded, or completely taken apart using basic hand tools.