Project Guide

How to Caulk Like a Professional

Item(s) have been added to cart.

Prepare the Surface
A person removing old caulk around bathroom sink with a utility knife.

A good caulking job starts with a clean surface. Take the time to remove any existing caulk to help ensure a good seal.

  • Cut old caulk out with a utility knife, razor blade, putty knife or scraper. 
  • Remove all paint, dirt, dust, grease and debris. If you’re removing silicone caulk, make sure all residue is completely removed. 
  • Use a rag to wipe the joint surface with rubbing alcohol or an over-the-counter disinfecting spray.
  • Rinse thoroughly with water and dry.

If the gap you are caulking is greater than 1/2 inch, press foam tape into the space.

Tape the Area
A person using painter's tape to mask around bathroom sink.

Caulking with tape along the surface will help produce an attractive finish. Apply painter’s tape to mask off areas around the joint where the caulk should not appear. This will give you a straight line of caulk and will improve the final appearance.

Cut the Nozzle
A person using a utility knife to cut the nozzle of a caulk tube.

Caulk is available in hand-held squeezable tubes or rigid plastic cylinders that require a caulk gun to push out the material. A squeeze tube is recommended for small projects, such as sealing a bathroom sink. See Step 6 for caulking tips when using a caulk gun for larger projects.

Some squeeze tubes may have a seal under the nozzle cap that will need to be removed or punctured before use. Follow the instructions on the tube and carefully cut the nozzle using scissors or a utility knife with a sharp blade. 

A line of caulk is called a “bead” and the width of bead is determined by where the nozzle is cut. To create a narrow bead, cut the nozzle close to its tip. For a wider bead, trim off more of the nozzle.

No matter how wide your caulk bead needs to be, cut the nozzle at a 45 degree angle. You will be applying the caulk with the tube at an angle, so cutting the nozzle on a slant will help get a smooth bead.

Apply the Caulk
A person applying new caulk around a bathroom sink.

Using a caulk gun is the easiest way to apply caulk. 

  • Insert the cartridge into the gun frame and make sure it's snug and secure.
  • Press the release at the back of the caulk gun and adjust the rod so the plunger is fully extended. 
  • Place the nozzle at a 45 degree angle where the sink and countertop meet.
  • Grasp the tube and squeeze with enough pressure to force the caulk into the joint.
  • At the same time, steadily draw the nozzle along the joint.
  • Apply steady pressure to the trigger or tube, and fill the gap with an even bead of caulk.
Smooth the Caulk Bead
A person smoothing new caulk around bathroom sink.

For a neat and professional-looking finish, “tool” or smooth the bead of caulk after sealing the joint. Lightly drag a caulk finishing tool over the bead to smooth it. Alternatively, you can simply use your finger. Moisten your fingertip in warm soapy water and drag it with light pressure along the length of the bead.

Whichever method you use, the overall goal is to smooth the bead and not to remove excess caulk.

If caulking with tape to mask the area around silicone caulking, remove the tape before the caulk starts to set. To remove the masking tape, lift the end and pull up at a 45 degree angle, away from surface.

Wipe away excess caulk with water and a damp cloth before the it dries. Regular caulk fully dries or cures in about 24 hours. Quick-curing products are also available. To remove excess dried caulk, use a putty knife to cut or scrape it away.

Caulking Tips
A person using a caulk gun to apply caulk between a vanity and wall.
  • When learning how to caulk a tub or another large project, use a dripless caulk gun for better results. This type of caulk gun releases pressure on the cartridge when you stop squeezing the trigger, giving you more control of the flow. 
  • The key to learning how to use a caulk gun is to start on one end of your project and try to work in a continuous direction.
  • Squeeze the trigger slowly to get caulk from the cartridge.
  • Use enough pressure to force caulk into the joint.
  • Steadily draw the gun along the workspace as you squeeze the trigger.
  • Release the trigger when it reaches the handle. It will spring back and you can then continue making a steady bead.

When you’ve learned how to use a caulk gun and how apply caulk around your home, shop online for the supplies you need. The Home Depot delivers online orders when and where you need them.