EnkaRetain & Drain 3211 for Green Roofs/Vegetative Roof Gardens

Water Retention Drainage Mat- Green Roofs love this stuff!

EnkaRetain & Drain 3211 was specifically designed for green roofs. This multi-function composite consists of a 40% post-industrial recycled polypropylene drainage core of fused, entangled filaments and a specially formulated water retention fabric bonded to one side.

Water Retention Fabric EnkaRetain 3211

This Drainage Mat:

  • Is made of entangled filaments that are molded in a square pattern.
  • The water retention fabric is a 14.7oz.yd² non-woven polypropylene fabric made of 100% post industrial recycled fibers.
  • This drainage mat will hold 15 times its unit weight of water.
  • The protection fabric eliminates the need for protection board and stops penetration and migration of bitumen membrane.
  • Inert to biological degradation and naturally encountered chemicals, alkalis and acids.
  • Can help to contribute up to 2 LEED points when used with other recycled content products.
  • When used as part of a green roof, ti can add towards additional LEED points by reducing storm water runoff, heat islands and energy consumption.

Features and Benefits:

green roof 3211 benefits
Enkadrain advantages image resized 600

Roof Gradient




5-20° (9-36%)

·     Runoff increases with roof gradient

·     Water runs off too quickly on steep slope, growing substrate can become dry especially near the top of the roof

·     Risk of sliding of green roof materials on the roof at high gradients

·     Use thin profile Enkadrains (0.25”) to slow down runoff and allow time for the rain to soak into the growing substrate

·     Use EnkaDrain&Retain to retain water and compensate for higher runoff


Technical Data of EnkaRetain & Drain 3211 for Green Roofs:

Physical Properties:
Green roof Enka Retain & Drain 3211 resized 600
Flow Rates:
Greenroof enka Retain and drain 3211 Flow resized 600

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