Caulk failure is the loss of the protective moisture seal due to the loss of initial adhesion and flexibility.
Good caulk will help you save energy, avoid moisture damage and prevent pest problems. The best caulk for the job depends on the situation. If you didn’t get it right the first time around, there are ways to improve and fix caulk failure.
There are three types of caulk failure: adhesive, cohesive, and substrate. Simply put, the bond between the caulk and the substrate can fail, the caulk itself can tear, or the substrate can break. Problems with caulked joints are commonly due to one of two errors. Either the substrate was not effectively prepared, or the wrong product was selected. Consider how it will be used before choosing a product.
First, consider what materials the joint is made of and how much movement it is likely to encounter. Silicone, for example, adheres well to glass and tile but poorly to wood. Paint won’t stick to pure 100 percent silicone caulk. Although products with different chemistries claim to be flexible, some are better suited for frequent joint movement. For most interior painting, 100 percent acrylic caulks, are recommended. They will seal cracks and adhere to most surfaces, even when moisture is present. Remember that caulk generally is not recommended for gaps that exceed .5″ wide at their midpoint.
To spearhead the problem from the beginning, try priming. Priming is essential for better adhesion, sheen uniformity and durability. The following Hirshfield’s products will ensure the caulk will have the best chance to succeed: #88-1250 Drywall Primer for the interior, Hirshfield’s #88-4250 Latex or #88-6050 Oil for exterior. Then select a top quality Hirshfield’s interior paint in the color and sheen of your choice.