Products / Hydrotech Blue Roof Assembly

Hydrotech's Blue Roof assemblies are protected membrane roofs built to hold rainwater on the roof for a time as a stormwater measure. The maker offers three versions: a stone ballast blue roof, in which water is stored in the voids of the stone and to a set depth above it, using heavier than usual ballast to keep the loose-laid Styrofoam insulation from floating, meant for utilitarian roofs without tenant use; an Ultimate Assembly blue roof, in which concrete pavers on raised pedestals leave void space for storage and heavier, thicker pavers hold the insulation down, suited to rooftop terraces; and a Garden Roof blue roof, in which the vegetated assembly sits on Permavoid structural void units (about 95% open space) that Hydrotech says are available exclusively through it. The MM6125 brochure lists the stone ballast build as stone ballast, stone filter fabric, Styrofoam, Hydroflex 30, Monolithic Membrane 6125, surface conditioner and approved substrate, and the PMR Planning Guide says a blue roof should ideally be installed on a flat, zero-slope deck.