RAM Drain 1241 is a composite polystyrene drainage medium with optional moisture retention capabilities often required for greenroof and planter box applications. Its one-half (1/2) inch high three dimensional core "thimbles" are covered on both sides with a polypropylene geotextile fabric.

When the RAM Drain 1241 used in a vegetated greenroof configuration, the fabric cover allows excess water to flow from the growing medium into the water storage cups, while preventing the growing medium sediment from entering. The fabric covering also retards root penetration into the drainage core, insulation and waterproofing membrane. Water retained in the storage cups is held until it is reabsorbed by the vegetation. Excess water is allowed to escape through holes in the top surface of the core and is carried off to the drainage outlets. The retained water will promote plant growth while reducing the chance of root rot due to excessive moisture. The open drainage channels also provide aeration for the plants root system. The fabric on the bottom side of the mat provides extra protection for Ram-Tough membrane systems. In a plaza deck application, moisture retention is eliminated by placing the mat with the reservoirs cups turned down. The top and bottom filter fabrics provide the same functions as in green roof construction.