31 Fiberglass Membrane

Karnak #31 Fiber Glass Membrane is a waterproofing fabric woven entirely of fiberglass yarn. It is ideal for use with cold application cements and coatings, and being of high flexibility, conforms to all contours and bends as required in general roofing and waterproofing maintenance.


  • ASTM D-1668, Fed. Spec. HH-C466b


  • (oz. /sq. /yd): 2.00
  • (lbs./36" x 150' roll): 6.5
  • Thread Count per Inch: 20 x 10


  • Warp (lbs./lineal inch): 75
  • Fill (lbs./lineal inch): 75


Karnak #31 Fiber Glass Membrane is treated with a synthetic resin in the proper balance to give complete compatibility with asphalt or tar and all accepted waterproofing and coating compounds.


  • Contour flexibility without cracking
  • High tensile strength
  • Will not mildew, rot or decay
  • Acid and alkali resistant
Weight and tensile strength figures are nominal values. Production variations limited to plus or minus 10% of these figures.


Available in the rolls packaged in cartons in the following quantity.

36" x 150' 6
18' x 150' 6
12' x 150' 6
9" x 150' 12
6" x 150' 12
4" x 150' 18

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Kanopy Reflective Roof Maintenance Solutions
  • Reduce Energy Use
  • Lowers Peak Energy Use, reducing energy costs year-round
  • Helps the environment, reduces "Heat Island Effect"
  • Extend the life of the roof
  • Reduces waste. Helps avoid roof tear-off.
  • Economic compared to roof replacement
  • Eliminates interior building operation disruption