A waterstop is a material embedded in the concrete, with the singular purpose to obstruct the passage of water through the joint. In other words, it is not an elastomeric sealant adhered to the exposed surface of 
a joint. Beyond the joint, waterstops cannot prevent migration of water vapor or capillary moisture potential through a concrete slab to protect the flooring system (e.g. hardwood or tile) from adhesion failure or deterioration. Similarly, waterstops are unable to prevent water ingress through cracks that develop in the concrete due to building settlement or live load deflection—waterproofing membrane systems, vapor retarders, and other construction products are available to the specifier and contractor for these issues.