TerraDrain Sheetdrain (Prefabricated Drainage Composite)


Sheetdrain – Prefabricated Drainage Composite

TerraDrain is a dimpled plastic sheet that provides effective drainage and waterproof membrane protection on foundation walls and other underground structures.

The integrated non-woven geotextile covering the dimples prevents soil particles blocking the drainage sheet, creates an air gap for reliable ventilation and allows inflow. Its dimple structure effectively captures and transports high water volumes whilst resisting high loads from earth and formwork.

TerraDrain TD10 & TD18 perform a multi-faceted role by providing protection for waterproofing systems and managing sub-surface water around building foundations. Soil backfill is retained by a filter fabric while allowing water to pass into the drainage core providing hydrostatic relief. Collected water is then conveyed to a proper collection system.

TerraDrain TD10 & TD18 each consist of an impermeable polymeric sheet, cuspated under heat and pressure to form a high flow dimpled drainage core. Cuspation/dimples can be on one side giving a flat surface on the opposite side (TD10) or cuspated/dimpled on both sides (TD18). The core is then bonded to a layer of non woven filter fabric. The filter fabric retains soil or sand particles as well as freshly placed concrete or grout, allowing filtered water to pass into the drainage core.

The double cuspated (TD18) provides an additional void space between the wall/wall membrane and Drainage Composite for air and water to circulate. In addition it maintains a very high flow rate while providing a higher compressive strength for greater depths.


  • Basement Foundations
  • Retaining Walls
  • Planters
  • Bridge Abutments