5 Most Common Caulking Mistakes

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When the time comes for you to pick up that caulking gun and seal a shower or lay a new bead on an exterior siding seam, watch out for these aggravating pitfalls.

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Anyone who owns a home eventually faces the inevitable: A dried, cracked or flaky caulk seal. These can appear nearly anywhere in your home, inside or out.

Of course, the number one pitfall is never using caulk around your home. Caulk eventually fails and that means water getting where it shouldn’t causing expensive damage) or energy loss (also expensive) because air can move freely in and out of your home.

When the time comes for you to pick up that caulking gun and seal a shower or lay a new bead on an exterior siding seam, watch out for these aggravating pitfalls.

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Don’t Skip Prep

The first common mistake happens before you even open the tube of caulk. Without proper surface preparation, your new caulk will not last. As tempting as it is to quickly lay a new bead and forget about it, you do need to completely remove old caulk, flaking paint or crumbling grout; repair any surface damage and then lay the new bead.

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Cut Right

When you open a tube of caulk, the tapered tip on each tube allows you to custom-size the opening for your specific job. Many people cut the tip and start caulking without regard for the width of the crack they plan to seal. This results in too much material on the surface, poor adhesion and/or a sticky mess. Cut your tip slightly narrower than the opening and use pressure and speed to adjust the width of the bead.

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Mind the Gaps

When it comes to width, another pitfall emerges—filling large gaps with caulk. Openings wider than one-quarter inch or more than one-half inch deep require backing material, such as foam rope. Pumping a huge crack full of caulk is expensive and affects product performance. Backing material optimizes the thickness of the bead and allows for the best cosmetic finish.

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Practice Patience

Many people charge right in, applying material immediately to the task at hand. Creating the best looking, most effective bead of caulk takes some skill. Instead, grab a grocery bag and practice a bit to get a feel for pressure control and how the bead comes out of the tip. Consistency is key. A derivative of this is jumping into a long bead without a break. Near the end, you may run out of space for the caulk gun. A sudden stop results and your carefully crafted bead becomes a mess. Work from each edge to the middle, or start by caulking the last 6 inches first. Do your best to keep pressure, speed and angle consistent.

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Don’t Forget the Final Step

The last common pitfall involves finish. So, you laid the most even, beautiful bead out of the tube. Looks great, you must be done, right? Wrong. Don’t miss the final critical step in the process: Tooling. Don’t get fooled by terminology here. Most of the time, the only additional caulking tools required are a fingertip, some water to dip it in and some paper towels. Smoothing the bead with light, steady pressure from your fingertip (or an ice cube or the back of a metal spoon for exterior caulk) does two things—it forces the caulk firmly against both surfaces and creates a clean, tidy appearance.