Bentonite combined with 20-mil virgin HDPE for dual waterproofing protection.

Bentonite clay is volcanic ash that expands when wet, absorbing several times its weight in water. The property of swelling makes bentonite unique as a sealant for below-grade waterproofing or as a liner for water retention. The TegraSeal membrane combines the swelling properties of bentonite with the strength and protection of HDPE sheets to form a self-sealing waterproofing membrane. The tough HDPE membrane provides the primary waterproofing envelope while the expandable bentonite clay provides the self-sealing insurance, even under hydrostatic conditions, necessary for a complete waterproofing system. Because both the bentonite clay and the HDPE membrane are known to be very stable below grade, TegraSeal waterproofing is expected to provide long-lasting protection for your building.


Technical Data Sheet


Product Brochure (PIB)

Decks & Tunnels

Backfilled walls/structures



TegraStop Waterstop

Seam Tape


Does TegraSeal meet the requirements for providing points on Leed and GreenGlobe projects?

TegraSeal Products will contribute to several LEED and GreenGlobe points. Contact TegraSeal for more information.

Under what conditions can a TegraSeal waterproofing system be installed in a “salt water” environment?

We recommend that you send in a water sample to TegraSeal for testing before using our product in salt