Sika injection waterproofing: PU or epoxy for a leaking crack?

# Sika injection waterproofing: PU or epoxy Water-reactive polyurethane systems and epoxy resins have different purposes. PU may be selected for suitable water-bearing cracks, joints or voids. Epoxy is generally considered for suitable stable cracks where filling and bonding are required. The choice depends on movement, water flow, concrete condition, crack geometry and the injection procedure.