The mastic joint (caulking) between the swimming pool concrete decking and the pool coping/bond beam is an extremely important component of a swimming pool and must be properly installed.
This joint has two purposes: · To isolate concrete deck movement from the pool coping/bond beam assembly. Concrete flat work including pool decks expand and contract with temperature change (up to 100° of variation can be expected). · It acts as a waterproof expansion barrier between the pool and the deck. If the caulking is not in good condition water travels underneath the coping down behind the pool tiles. The tiles can lose their bond to the pool wall, get loose and eventually fall off. The finished product is a pool sealant that has a flexible, grout-like appearance that is pleasant to the eye, sustainable and long lasting. The mastic joint (caulking) between the swimming pool concrete decking and the pool coping/bond beam is an extremely important component of a swimming pool and must be properly installed.