PUBLIC GARDENS - Calhoun School Greenroof

For this project a waterproof liner was necessary to make the trickle irrigation of the lawn area possible. The heavy liner, which was custom sized to fit the lawn, is rolled out and adjusted. (NEXT)

Since most of the roof drains are located within the lawn area, which is separated from the rest of the roof, the proper channeling of runoff water posed a challenge. The runoff from outside the lawn area reaches the drains underneath the waterproof liner. The waterproof liner is cut around the drains to enable excess water from to lawn to drain as well.

The lawn will be irrigated from below using trickle irrigation. For this type of irrigation to work some water has to remain on the bottom of the planting bed, in the coarse substrate. Therefore low "dams" where created around the drains to keep the water from draining entirely. (NEXT)