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Greenroof - Roofscapes®
Drainage, Water Retention and Aeration

To help create a sustainable environment for plantings, precipitation water is controlled through a combination of drainage and retention mediums which also provides additional aeration for the plants. The specific soil depth and vegetation design will influence the grade and degree of water retention materials.

The alternating balance between good drainage and the retention of a supplementary water supply for plantings and root aeration are addressed with Ram-Drain and Retention mats.

Ram-Drain and Retention Mats 1241 and 2451 and Ram Retention 2500 are manufactured with small integral reservoirs providing for improved plant hydration while allowing complete drainage and air flow around the reservoirs simulating a natural planting environment. Ram-Drain 36R does not have any integral reservoirs and is solely used for expedited drainage. Retention Mat 440 is a high loft fabric designed to act like a diaper, keeping water in its place on greenroofs.

Drainage, Water Retention and Aeration Materials

Ram-Drain 36R is for use with plaza decks and planters;
  0.45 inch thick drainage mat (non-woven mesh style)

Ram-Drain 1241 is for use with low profile systems (extensive);
  Water Retention – 0.06 gallon/ft²

Ram-Drain 2451 is for use with high profile systems (intensive);
  Water Retention – 0.11 gallon/ft²

Ram-Retention 2500 is for use with high profile (intensive);
  2 inches thick water retention (filled with drainage material) – approx. 0.56 gallon/ft²

Ram-Water Retention Mat 440, more than ¼ inch thick the fabric has an initial retention
   of 0.18 gallon/ft²

Ram-Aeration 600 is for use over insulation to expedite drying time; 0.25 inches thick

Greenroof–Roofscapes® 1241 and 2451 drainage and retention mediums have a geotextile mat on both sides. A heavy polyester geotextile mat on the bottom acts as an additional protection layer for the membrane as it cushions the load of the overburden. The top polyester geotextile fabric acts as a filter media to prevent soil migration into the retention reservoirs and drainage channels. Ram-Retention 2500 is a plastic panel made from recycled high density polyethelene and offers top and bottom sided diffusion with open channel drainage. Ram Retention 2500 is filled with pea gravel for structural stability and requires Poly Felt 3.5 Filter Fabric cover. Ram-Drain 36R has one geotextile mat on the topside of the entangled fiber mat drainage.

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Last Updated : 1.27.2016
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