Drainage and Protection Board

TREMDrain® DPI is an optional drainage, protection and insulation board designed for use primarily with TREMproof® 260 Spray-Applied Waterproofing Membrane. TREMDrain DPI’s unique and proven glass fiber design promotes efficient water drainage and the retention of the board’s Rvalue. The semi-rigid nature of the board acts as a protection course for the TREMproof 260 waterproofing membrane.

TREMDrain DPI is an excellent way to address below-grade energy efficiency needs. It fulfills requirements specified in ASHRAE 90.1 which call for belowgrade walls to have “a rated R-value insulation not less than” what is specified for the climate zone.


  • TREMDrain DPI is installed in vertical applications, where TREMproof 260 has been applied to typical applications such as foundation walls, tunnels, and planters
  • TREMDrain DPI protects the waterproofing membrane, channels water to the drainage system and insulates foundation walls
  • The exterior insulation of foundation walls can reduce interior condensation by increasing the outside temperature of the wall, helping move the dew point nearer to the outside of the wall. TREMDrain DPI may help reduce the risk of freeze/thaw related damage on typical foundation walls
  • TREMDrain DPI allows for same day and efficient installation of the drainage, protection and insulation course when used with TREMproof 260