It'd be great if there was one caulk or one adhesive that did it all. But for nearly every job there is a specific caulk, adhesive or glue. And while they often are thought of together, they can't always be found together. You'll find them distributed throughout a store and grouped together by application.
For example, look near the paint aisle and you'll find the caulk section. Head over to tile and flooring, roofing and masonry, and there will be a nice selection there as well. The location of glue and other adhesives also range widely, but often occupy a smaller section near the paint, with some construction adhesives found next to the caulk in a completely different aisle.
But there is a method to the madness, and it just takes a little savvy to make sense of it all.
We all want a “tight” house with no drafts or leaks so we save money on energy bills and keep out moisture to avoid water damage and mold. We also want our water-laden areas — the kitchen and bathroom — to keep water where it belongs.
For bathrooms you'll need caulk labeled for tub and tile. These are formulated for high-moisture areas and resist mold and mildew. Within this type of caulk are several variations, included sanded ceramic-tile caulk, which is available in colors to match the color of your grout so you're not limited to bright white or clear caulk.
Caulk for use around doors, windows and molding will be clearly marked. Generally, the same caulk can be used for all of these applications. Make sure that the product you get is labeled as paintable because paint will not adhere properly to certain types of caulk — it will bead up like oil trying to mix with water. For outdoor applications, select caulk rated for exterior use. Most often these will be either silicone-based or an acrylic blend with silicone added. Image 1 shows three varieties of caulk including: tub and tile; paintable acrylic blend window, door and molding; and silicone window, door and molding.
Although it can be tempting, caulk shouldn't be used as a filler. For gaps larger than 1/4 inch, you'll need to use a spray foam or backer rod to fill larger gaps, and then follow up with caulk. Backer rod is usually found with weather stripping.
Most caulk comes in a tube that requires a caulk gun, which consists of a “trigger” that drives a plunger pushing the caulk through the tube toward the tip. Caulk guns are a must-have and range from just a few dollars to $12 or more. They all perform the same function, so there's no point in buying the most-expensive caulk gun unless you're a pro. Your best bet is a midrange gun at about $6. Some of the cheaper ones — less than $3 — can stick and have to be taken apart and reassembled frequently, which is not something you want to do in the middle of a job.