Types of Geocomposite Drainage System

Geocomposite Drainage System typically includes the combination of two or more materials, one of which is geosynthetic. Generally, drains may also be an arrangement of different drain types. The first type includes “Entangled Polymeric Filament Mats”. The mats are composed of entangled filaments of different polymers which allow water flow from any direction. Usually mats have a geosynthetic filter attached to one or both sides. Second type is “Shaped Plastic Membranes”. These drains are composed of regular sheets of different polymers deformed to generate dimples, studs or pegs. Some types also allow drainage to happen on one side of the membrane. On the other hand, other varieties support drainage capacity on both sides of the membrane as well as water holding.

Normally these drains have a geosynthetic filter attached to one side. Another type is “Porous Synthetic Mats” which are made of fabrics or non-rigid foam compressed together and frequently from recycled materials. These drains come with or without a geosynthetic filter. The last type of geocomposite drainage systems are “Rigid Grooved or Deformed Foam Boards”. These drains are developed by using rigid foam boards with grooves or deformations on one side to allow drainage.

There are a number of factors that should be considered while evaluating drainage layers for green roofs. These factors include thermal stability, structural ability, and aggregate materials granular shape etc.