Paul Bianchina, Caulking techniques demystified
While caulking seems like a pretty easy thing to do — and all in all it is — there are some tricks of the trade that can make a big difference between a smooth, hassle-free caulking job and one that’s frustrating and perhaps a little sloppier than you’d like.
A few simple tools
Your caulking job starts with a good-quality caulking gun.
Ignore the temptation of those inexpensive guns that utilize a ratcheting plunger, easily recognized by the series of notches cut into the plunger’s shaft. They don’t operate smoothly, so it’s hard to apply a clean, uniform bead.
Instead, for about $10 to $12, you can buy a pro-grade gun that will last you a lifetime. It has a couple of moveable plates that grip the plunger rod, giving you a smooth action with a clean release that doesn’t waste material by letting it drip out of the end of the tube. The best ones also have a rotating barrel, a rod for puncturing the caulking tubes, and hook on the end for hanging the gun.
In addition to the caulking gun, you’ll need a 5-gallon bucket, several rags, a utility knife, and some disposable gloves. If you have large gaps to fill, you’ll also need some foam backer rod, as described below.
Prepare the joints
If the area to be caulked is dirty, dusty, wet, or filled with debris, you won’t get good results, so begin by using a brush, putty knife, compressed air, or other tools to clean out the cracks you want to caulk. If you’re also repainting, be sure that any old paint is cleared out. On new wood, be sure the wood is dry and free of sawdust, and has shrunk as much as possible.
The manufacturer’s directions on the caulking product you’re using will specify how large of a gap that particular caulk will fill — typically 1/4 to 3/8 inch in width. If you try to fill anything wider that what the caulking is rated for, it will simply sag into the gap or the caulk film will split. Either way, the result will be an unsightly caulking job that’s not weathertight.
The solution is to use what’s known as a backer rod, which is simply a round foam rod, sold by the roll in different diameters. Use a rod that’s slightly larger in diameter than the gap so that it compresses into the opening. Cut the rod to the desired length, then press it into the gap so that it’s slightly below the surrounding surfaces. You can then caulk the gap on top of the backer rod, without worrying about the caulk sagging into the gap.
One of the easiest ways to ensure that the caulking bead isn’t too large and sloppy is to keep the bead small in the first place. To do that, cut the end of the caulking tube to create an opening that’s no larger than the bead you would like to produce. Also, cut the tube at an angle, rather than straight across. A small, angled opening in the tube will produce a bead that’s clean and easy to control.
Another method for keeping your caulking beads from getting sloppy is to keep the end of the tube clean and free of dried caulking. A simple and convenient trick for doing that is to fill a 5-gallon bucket with enough clean water so that you can hang the caulking gun from the edge of the bucket by its hook and have the end of the tube suspended in the water. That allows you to easily transport and store the gun and tube while you’re working, without the tip ever drying out.
To apply the caulk, start at one end of the gap you’re caulking, then pull the gun toward you as you gently squeeze the trigger. Getting a clean bead is a matter of the right combination of trigger pressure and gun speed, but it doesn’t take much to master the technique.
As you approach the end of the bead, let up on the trigger pressure, and as you come to the end, press the release button to relieve the pressure on the tube and stop the caulking flow. There’s often still a slight flow of caulk out of the end of the tube even after releasing the pressure, so have a scrap of cardboard around to set the gun on, or just hang it back in the bucket.
After applying the bead, you can leave it alone, or smooth it out with a tool or just with the tip of your finger. If you choose to use your finger, wearing disposable gloves will save a lot of washing up later. Also, when using your finger be really careful about picking up splinters or cutting yourself on nails or even the sharp edge of old paint.
Keep a damp rag with you at all times. It’s the only way to keep your hands, your equipment, and any adjacent surfaces clean. Rinse the rag often, because it will quickly begin to stiffen up as it gets caulking on it.
You’ll also find that after a short time, rinsing won’t do much good any more, and that’s when it’s time to change both the rag and the water in your bucket. If you remember to do both, you’ll find that your entire caulking project runs a lot smoother, and everything stays a whole lot cleaner.
Didn’t use up the entire tube of caulking? Here’s a good trick for keeping the remaining contents from drying out. Take a piece of plastic wrap, fold it over a couple of times, and secure it over the end of the tube with a rubber band or some tape. Then squeeze a bit of caulking out of the end of the tube so it makes a glob inside the plastic wrap. That glob of caulk will harden inside the plastic wrap and make an airtight seal on the end of the tube, keeping the rest of the tube’s contents from drying. When you want to use the tube again, just remove the plastic and pop the dried glob off the end.
Have a home repair or remodeling question for Paul? He can be reached by email at email@example.com .