A word about caulking.
In the industry, we throw the word “caulk” around as a general word for “sealant”. It is imperative that you get the right sealant for the right job. I’ve been in a lot of houses for repairs to the bathroom and kitchen areas because of water ingress or leakage. The most common problem that I see is the improper use of silicone. In wet areas (tub, shower, kitchen backsplash, e.t.c.) the correct sealant to use is a 100% joint rubber silicone (It should smell like vinegar fresh out of the tube). As the different surfaces (tub to tile or surround or countertop to tile) expand and contract, it’s the rubber and the acetic acid (the vinegar like smell) that allows the expansion to happen without losing the adhesion. Another place that I’ve seen silicone used incorrectly is on the exterior of the house – typically around the chimney and windows. Over the years, the stucco around these two places has become cracked or something has shown up in the form of a leak. Silicone is NOT for exterior use. The ultraviolet rays from the sun hit it and, in a matter of hours, renders it useless.
One downfall of the silicone the working with it – an inexperienced hand (or a finger, truly) can make quite a mess. Painting 100% joint rubber silicone with latex paint is not possible, an oil based paint is necessary.
When in doubt, ask your supplier for the right sealant. You may not need silicone.