Green Technology

The Fencing Academy of Phildelphia has a " ...3000 square foot green rooftop ... of perennial sedum varieties ... installed ...  in the spring of 1998.  ... was a retrofit design with the performance objective being the restoration of the pre-development hydrology for the 2-year return-frequency storm."

" ... reached a mature stage of development, creating a meadow-like setting of perennial Sedum varieties ...  selected to withstand the range of seasonal conditions typical of the Mid-Atlantic region without then need for irrigation or regular maintenance. ..."

" ... cover is only 3.4” thick, including the drain layer, and weighs less than 5 lb/sf when dry, with a maximum saturated weight of under 17 lb/sf. ..."

Via:  LIP Urban Design  Link