This semi-intensive roof garden incorporates a Fytogreen lightweight topsoil mix and Hydrocell RG30 sub-topsoil water reservoir layer. Located on the 4th floor, the 750sqm lawn of tall fescue grass has limited root zone depth due to the engineering design constraints in addition to the requirement to have a limited step down to the surrounding paving. The profile has 25mm Fytonop drain layer, 2mm geofabric layer with a 60mm Hydrocell RG30 sub-topsoil layer, and 80mm Hydrocell 40 podium composite mix layer.