University Town, National University of Singapore
To provide both intensive and extensive roof systems to enable the establishment of an accessible landscape roof at the lower deck and an inaccessible extensive green roof at the upper deck on the roof of the Education Resource Centre of University Town.
Landscape Roof, Sub-surface Drainage
VersiCell® drainage modules were installed directly on the waterproofing membrane to provide a drainage cavity beneath a geotextile filter fabric layer and the planting soil above. VersiCell® with high internal void and an open surface design is able to rapidly capture and transport excess water, preventing the green areas on the roof from becoming waterlogged. The drainage modules also provide a protection layer for the waterproofing membrane, prolonging its serviceable life.
Extensive Green Roof
VersiDrain® 25P drainage and water retention trays were installed directly over the waterproofing membrane. Geotextile filter fabric was then laid over the VersiDrain® 25P trays and a lightweight inorganic planting media, EnviroMix® GR, spread on top for in-situ planting of various selected drought-tolerant plant species arranged in attractive patterns. Water retained by the water reservoirs of the trays during wet periods is returned to the planting media by capillary action during dry spells and drawn upon by the plants to sustain vigorous and healthy growth
From their windows, students residing in the nearby Graduate Residences enjoy a refreshing, cool and aesthetically pleasing layered green roof instead of otherwise bare concrete roofs.