Caulking: Tips and Tricks for a Professional Final Touch

A DIYer caulking around a baseboard.

Your room is painted and your new moulding is installed. While this might seem like the optimal time to head off to the kitchen for some well-deserved refreshments, there is one final step that will take your painting project to the next level.

Caulking is an important part of any paint job that no professional painter would think of skipping. It’s a relatively painless process, and if you’re willing to get your hands a little dirty your investment of time and effort will pay dividends in your final result.

What Should I Caulk?

With a little bit of painter’s caulk you can vastly improve the final appearance of virtually any paint job. For interior applications*, I like to use a “Fast Dry” formula. You’ll pay a little more for it, but it could mean the difference between getting that coat of paint on tonight or having to wait until tomorrow. Before you paint your moulding, look for any gaps in your miter joints or where your moulding meets your wall or ceiling. Any gap ¼ of an inch or smaller is a candidate for caulk. There are many ways to fill bigger gaps, including wood putty or filler, but this article has some great tips for caulking gaps larger than ¼ inch.

It’s worth mentioning here that I like to use paintable wood putty for nail holes because it’s easier to get a proper fill on your first pass. You can caulk nail holes in a pinch, but it can be difficult to get a smooth appearance without having to go over the hole a few times.

*For exterior applications be sure to use a paintable caulk with added silicone, for weather resistance.

When Should I Caulk?

In short, there is no wrong time to caulk. On non-porous surfaces, painter’s caulk cleans up easily with a damp rag, and as the name implies you can paint right over it once it’s dry. Occasionally after the installation of new moulding, shifting environmental conditions in the home (like varying humidity levels) can cause wood moulding to swell and shrink. Here in the Northeast it's common to see cracked caulk joints in the days, weeks, or even months following installation. If this happens, do not despair. Instead, pick up your caulk gun and face your adversary head-on. If you do find yourself in this situation, you will first want to scrape out any existing caulk that might get between you and the perfect bead.

How Much Do I Use?

The first thing to keep in mind is, as the adage goes, “less is more.” Remember this especially when you're cutting the nozzle on your tube of caulk. With a sharp utility knife, slice off the tip of the nozzle at an angle (not straight across). This aids in ease and economy of application. I find that cutting a hole about 1/8 of an inch big produces a good bead for most small to medium-sized applications. Only tackle a couple of feet at a time, and apply just enough to cover the gap you are trying to fill. Remember that your bead doesn’t have to look perfect at this stage, but your cleanup will be a lot easier if you can avoid using too much.

“Tooling” for a Professional Look

Now is your chance to achieve caulking perfection. The tooling stage is all about removing excess caulk and shaping it to match the contours of the moulding or surface you are working with. You have the option of using a purpose-built caulking tool, but I find that a wet finger works just fine. Either way, you’ll also want a damp rag on hand where you can put the excess caulk that you remove. Keeping an eye out for potential splinters, carefully drag your finger down your bead of caulk, simultaneously forcing it into the gap and removing the excess. Use your dampened rag to clean any residue from the moulding and the adjacent surface. If you are filling a joint in moulding that has any sort of detailed profile to it, you will notice that it is difficult to get into those details with your fingers. A painter’s 5-in-1 is a great, versatile tool for working caulk into tough spots, but if you don’t have one of these on hand you might have to get creative. In this regard I’ve called upon everything from toothpicks and finish nails to credit cards and kitchen utensils, and they’ve all worked just fine.


Patience and persistence are the keys to mastering any skill, and caulking is no exception. Keep in mind that on a typical job even the pros have to make a second and sometimes even third pass to get the result they’re looking for. But any caulk is better than no caulk, so why not give it a go? I think you’ll be pleased with the results.