Bentonite swell strip
Bentonite hydrophilic swell strips, based on a specific natural clay or sodium bentonite with fast and high swelling capacity in contact with water, have been used for many decades in the construction industry to preventively and economically seal horizontal and vertical construction joints. SPETEC® BST300 is improved version where the bentonite is embedded in synthetic butyl rubber, specific fillers and crystallisation additives.
As a result, it can be used for complex joint structures and continues to seal perfectly even after repeated wet-dry cycles. The swelling capacity exceeds 300% and the seal can withstand pressures up to 7 bar. Fastening to the concrete structure can be done either by SPETEC® WT400 adhesive or by nailing. A metal fixing net SPETEC® BSTF for fixing with nails is available among the accessories.