What Type of Caulk Should I Use for the Kitchen Sink?
Silicone caulk should be used with a kitchen sink because it repels moisture and is resistant to mold and mildew.
Caulk is run around the edge of a kitchen sink to provide a waterproof seal between the sink and countertop, but it also has the added benefit of helping to hold the sink in place. Because of this, it's important to use the right kind of caulk on your kitchen sink.
Types of Caulk
Most caulks are made with either silicone or latex, with combinations of the two also available. Several different types of caulk serve a variety of needs around the home; for example, there are separate caulk types for concrete, windows and bathrooms, as well as interior and exterior types of caulk. Finding the right one can be confusing, but it is important to use the correct type for each application. For a kitchen sink, for example, use silicone caulk because the silicone repels water and moisture and is resistant to mold and mildew. Latex caulk, on the other hand, can break down and become brittle and ineffective after repeated exposure to water. White, almond and clear caulk are commonly used colors with kitchen sinks.
Uses on Different Sinks
The caulk you'd use would also change depending on the type of kitchen sink you were working on. You'll find two main types: drop-in and undermount. A drop-in kitchen sink is dropped in from above, while an undermount sink is mounted under the countertop using metal anchors and epoxy. A bead of caulk is usually run along the edge of a drop-in sink after installation, with any excess cleaned with a wet towel. The exception is a stainless steel sink, which is held in place with clips. A bead of caulking or plumbers putty is usually run along the bottom edge of a stainless steel sink before it is dropped into the countertop and fastened into place with the clips. On an undermount sink, a bead of clear silicone caulk should be placed around the flat lip of the sink. While caulk will help hold a drop-in sink in place, it is used only to seal an undermount sink and not used in place of epoxy.
Applying Caulk to the Sink
Before applying caulk to a kitchen sink, the area must be clean and dry because caulk will not stick to old caulking or wet surfaces. This means removing any old caulking with a utility knife or putty knife if you are replacing a kitchen sink. Clean up hard-to-remove pieces with rubbing alcohol. If the sink is a new install, wipe the area well with a cloth before installing. Purchase caulk in either a squeeze tube or a cartridge that fits inside a caulking gun. A longer bead of caulk can be run with a caulking gun cartridge, while a squeeze tube is smaller and sometimes easier to maneuver.
Gary Sprague is a retired master plumber who now works as a writer. He lives with his family in Maine.