TerraDrain® Sheet 101 Series

TerraDrain® Sheet 101 & 121 prefabricated drains are constructed using a formed polystyrene drainage core with a nonwoven filter fabric bonded to one side. The filter fabric is bonded to each dimple to prevent soil intrusion into the flow channels while allowing water to freely enter the drain core from one side.

TerraDrain® Sheet 121 provides additional protection for soft waterproofing membranes. The high-strength polymeric film is bonded to the flat side of the drainage core to prevent membrane intrusion into the back of the dimple.

Metric Values

All values provided are intended for rapid comparison purposes, only. Please refer to a specific product’s Product Data Sheet (PDS) and the disclaimers therein for a detailed listing of all characteristics, associated definitions and values needed for structure design, specification compliance review and product submittal purposes. Please Download PDS for all information transfer, printing and submittal purposes.

Property Test Method Units TerraDrain® Sheet 101 TerraDrain® Sheet 121


Material 1
Water Flow Rate
ASTM D4491 gpm/ft2 165 165
Grab Tensile Strength
ASTM D4632 lbs 100 100
CBR Puncture Resistance
ASTM D6241 lbs 275 275
Apparent Opening Size
ASTM D4571 US Std. Sieve 70 70
Grab Elongation
ASTM D4632 % 70 70
UV Resistance
ASTM D4355 % @ 500 hrs 70 70


Material 1
ASTM D1777 in 0.44 0.44
Compressive Strength
ASTM D1621 lbs/ft2 15000 15000
Flow Rate 2
ASTM D4716 gpm/ft 17 17
Product Data Sheets

  • 1   PP = Polypropylene; HIPS = High Impact Polystyrene
  • 2   In-plane flow rate measured at 3,600 psf (172 kPa) compressive load and a hydraulic gradient of 1.0.