Designing a pool on top of a pre-existing building isn’t a walk in the park; it can be more like jumping off the deep end. Dan Ball, principal of Genco Pools, Greenville, S.C., was commissioned to install a rooftop pool and hot tub on top of a parking ramp at The Hub, an upscale apartment complex for college students in Columbia, S.C. “Concrete would be too heavy for this project to work at all,” says Ball, who turned to ACH Foam Technologies of Denver, Colo., for a structural geofoam product that would lighten the load.
ACH Foam Technologies’ expanded polystyrene (EPS) Geofoam is an engineered lightweight material with high compressive strength (18.6 pounds per square inch at 1 percent deformation) and predictable performance. It has become a staple material for roads, embankments and other civil infrastructure, but architects and engineers are using it for everything from structural underslab foundation fill to pool profile fill to structural support for levees.
Swimming pools have both deep and shallow ends, but rooftop swimming pools have those ends at different heights. Engineers must install support material at the shallow end. Using a range of Geofoam products (EPS39, EPS22 and EPS 15), Genco Pools supported the pool on 6 to 36 inches of foam fill that conformed to the curved, 3-D geometry of the pool design. Geofoam also expedited pool installation time, meeting a tight timeframe.