Urban Agriculture Products

Urban Agriculture Products

Product has a data sheet (PDF format)

Filter Fabric and Drainage

Filter Fabric

Beneath the growing media and above the drainage system, the filter fabric keeps the media from clogging up the drainage while allowing water to flow freely. Green Roof Solutions has a 3.5-oz filter fabric, FF35. An important consideration with filter fabric is the flow rate while preventing media runoff. The GRS FF35 has a high flow rate of 150 gallons per minute per square foot. The FF35 is a needle-punched fabric composed of virgin polypropylene staple fibers that are randomly arranged and needle-punched to form a cohesive geotextile. GRS filter fabric is resistant to UV degradation and to biological and chemical environments found in soil.


Green Roof Solutions offers many different drainage layer options, depending on system goals regarding water retention. The most critical role of the drainage layer is to provide adequate flow of water off the roof during and after a rain event. The design of the different drainage layers allows for a portion of the stormwater to be retained above where the water is allowed to flow freely off of the roof. The systems are designed to ensure that stormwater can be used by plants for longer periods of time without oversaturation of the system. This promotes plant growth, avoids anaerobic soil conditions, and keeps retained water from pooling on the roof.

GRS drainage products typically fit into a green roof system above GRS Root Barrier and below GRS filter fabric. Depending on regional precipitation rates and the water retention goals for your specific project, Green Roof Solutions has a full range of products to meet your needs.

GRS drainage products include GRS filter fabric, GRS drainage panels, GRS drainage layer composite cores, and GRS Aggredrain.

All products made in the United States unless otherwise noted