Design Questions


EPDM has a proven track record in various waterproofing and pond lining applications which somewhat resemble roof top applications. However, there are certain rules that should be followed when designing a roof top garden regardless of the type of membrane used:

  • Select a membrane with high puncture resistance
  • Establish redundancy in the waterproofing assembly by overlaying splices
  • Design the assembly to provide slope and proper drainage at the membrane level
  • Incorporate protection above the membrane to aid against root growth and possible puncture
  • Incorporate a drainage layer and a root barrier to influence root growth away from membrane
  • Select proper growth media for the type of roof garden intended

What applications are suitable for EPDM membrane?

EPDM membrane can be used for low and steep slope roofing, as well as unusually shaped structures (such as domes, barrels and other geometrically shaped roofs) due to its versatility. The membrane can be adhered, mechanically fastened, or loose laid. It can be installed above or below insulation (i.e., an IRMA application), and can also be used in below grade waterproofing applications.

Unlike most asphalt base products that are limited in their installation to a fully adhered application and have restrictions of ponded water, EPDM membrane can be used successfully in exposed or concealed assemblies due to its ability to withstand temperature extremes and resist the absorption of moisture.