How to Apply Caulk Properly

Proper application of caulk starts with cutting the nozzle at a 45-degree angle. Insert the tube in the caulking gun, and remember to pull, don't push, the caulk along the joint. Continue to fill the joint, making contact on both surfaces. Keep in mind to only apply 2-3 feet of caulk at a time so you will have enough time to tool each section.

Step 1: Cutting The Nozzle: Embossed markings are located on each tapered caulk cartridge nozzle that correspond to the size of the bead that can be dispensed when the nozzle is cut at each marking. By cutting the nozzle at different measurements, you can form a caulking bead to match your joint size. It's easy - just cut the nozzle at a 45-degree angle, place it in a caulking gun, and you're ready to begin (except that most cartridges have an internal foil patch at the base of the nozzle that needs to be punctured with a nail).

Step 2: Getting Started: Before you actually start to caulk, do some test caulking on a newspaper or paper towel to get a better feel for how the product dispenses. It is especially important to get the feel for keeping the caulking gun moving smoothly as you complete one stroke of the trigger and begin the next stroke. Once you've run a few inches or feet of caulk and have a good sense of what to expect, then start your first caulking effort on a part of the house that is relatively out of the way and unnoticed. Then, by the time you get to those portions of the house that are more conspicuous, you will have developed a good level of skill and your results will show it.

Tip: It is far better to pull the caulk tube nozzle along the joint than to push it. Pulling it allows the nozzle to smoothly slide over any obstructions on the surfaces being caulked, while pushing usually leads to more hang-ups and sudden stops with attendant "blobs" of caulk occurring. Keep in mind that if you "mess up" a section of a bead, you can scrape it out right away and start over.

Step 3: Applying A Bead of Caulk: As you apply the sealant, hold the caulking gun at a 45º angle to the joint being filled. Orient the nozzle opening so that it forces sealant into intimate contact with the joint surfaces. As you finish applying each bead of sealant, relieve the pressure inside the tube by releasing the trigger and pulling back on the rod to stop the flow of caulk. (Releasing the trigger alone will not stop the caulk from flowing out of the nozzle.) Apply only about 2-3 feet of caulk bead at a time so that you will have enough time to get it "tooled" before it begins to "skin" over (which then makes tooling difficult or impossible).

Step 4: The Art of Tooling: "Tooling" the bead ensures good adhesion and a good look. "Tooling" is the process of gliding over the entire length of the applied bead of caulk in order to smooth it out and further force the thick caulk into enough intimate surface contact to establish good adhesion. Tooling can be done with a finger - covered with a latex glove, wetted with some water or solvent or just bare, depending on the caulk used - or with various tools like a spoon, shaped piece of wood or a foam paint brush. It is important to avoid scraping an excessive amount of caulk out of the joint during tooling to avoid starving the joint for sealant and wasting a lot of caulk. Keep rags handy to clean up any mishaps, and clean up any problem areas right away since it is much more difficult to clean up dried caulk later. If masking tape is used along the sides of the joint, make sure the tape is removed immediately after tooling is complete and before the caulk skins over, so that it will pull away cleanly and leave a smooth, even line.