ABSTRACT
Adhesion and cohesion are the two most important characteristics of a sealant. The sealant must stick to the walls of the joint. If it does not stick, water will work its way behind it and movement will cause the sealant to pull away from the surface. Without adhesion, a joint fails. Cohesion is equally important in all cases, except where the joint simply does not move. If the sealant does not have integrity-if it pulls apart during movement-the joint will surely leak. The most common cause of failure is loss of adhesion with all generic types of sealants.
