TABLE OF CONTENTS The category sealants spans a wide range of construction activities and applications from preventing water and moisture from infiltrating into below-grade structures to maintaining the watertight integrity of the entire superstructure.
This section deals primarily with caulking and sealant compounds: selection and application, and, secondarily, curtain wall and masonry sealants.
These materials generally fall into one of three categories:
Dynamic joints Joints that exhibit changes due to movement from expansion, contraction, isolation and loadings.
Static joints Joints that exhibit little or no movement, such as masonry mortar joints. However, no joint in a building is truly static because all materials exhibit some movement from temperature changes and load factors.
Butt joints Joints that have opposing faces that contract and expand and place a sealant in compression, tension, and can also exhibit shear from extreme loading forces or seismic events.
The key to proper application of any sealant begins with proper surface preparation, which can vary considerably from one material to another. Most manufacturers go to great lengths to provide detailed surface preparation and application procedures, which are often ignored by the applicator, resulting in either poor performance or outright failure.
The following general guidelines are to be augmented by the manufacturer s instructions for the sealant and surface selected:
Concrete and masonry Concrete can have the most variable surface conditions of any product because of variations in curing conditions, moisture content, finishing techniques, additives, hardeners, curing compounds, and...
