Swellable tape consisting of sodium bentonite embedded in a matrix of non-vulcanized rubber as binding agent. In contact with water it develops volume by swelling up to 340%. As a result it seals and waterproofs the joint gaps permanently.
WATERSTOP 1520 is used to underground constructions for sealing horizontal or vertical construction and connection joints in concrete elements, around pipe penetrations in walls, etc.
The substrate must be clean, dry and free of loose particles. Place WATERSTOP 1520 bentonite swellable tape in centre of the joint. The subsequent concrete covering should be at least 8 cm on all sides. Position the swellable tape correctly. Fasten using corresponding nails wither by hand or mechanically using a bolt-firing tool. The distance between nails should not excees 20 cm in the longitudinal direction of the swellable tape. Both straight and angle joints need to be butt jointed. The joint areas must be form-fit in order to avoid any discontinuity in the system.