How to Apply Silicone Caulk

  • 2-4 hours
  • Beginner
  • 20-50
What You'll Need
Silicon caulk
Caulking gun
Utility knife
Putty knife
Latex glove (optional)
Clean rag

The application of silicon caulk is a regular task for the do-it-yourself handyman. From jobs as diverse as sealing the tile in a bathtub to filling a gap between a wall and baseboard, silicon caulk is a very versatile product. When you need to apply silicon caulk, you have to know how best to do it. While it may seem sensible to work slowly, squeezing out a bead of caulk that fill a gap perfectly, actually it is best to move confidently along a seam quite quickly. You’ll have to work the caulk into the seam after application, so don’t spend too much time focusing on the perfect bead.

Step 1: Remove Old Caulk

If there is an old, dry bead of caulk already located where you need to reseal, you will first have to remove it. There is no easy way to do this. You simply have to get underneath it with a scraping device such as a putty knife. Sometimes you can pull up a large amount of it at once, but you’ll likely have to scrape along the entire seam until the old caulk comes off.

Step 2: Load Tube into Caulking Gun

Next, place the new tube of silicon caulk into the caulking gun. Pull the plunger arm of the caulking gun all the way back. Insert the nose of the tube through the hole in the front of the gun. Squeeze the trigger and push the plunger arm snugly but not too tight against the back end of the tube. Take your utility knife and cut off the tip of the tube’s nose. Cut it at a slight angle, but do not cut it too large. The resulting hole should be less than ¼ inch. Squeeze the trigger until the plunger tightens up against the back of the tube and silicon caulk starts to squeeze out the tip.

Step 3: Apply Bead of Caulk

Hold the caulking gun at about a 30-degree angle with the angled cut on the tip flat against the seam. Pump the trigger until you feel resistance. Squeeze the trigger and run the gun confidently over the entire seam, applying an even bead as you do. Run the bead about 2 to 3 feet before stopping. Confidence is key. Don’t stop to fill gaps that arise.

Step 4: Work it in with Your Finger

After the bead is applied, go over it with your finger to make a concave seal over the seam. Working it in with your finger will prevent any large sections from missing any material. Wear a latex glove if you have sensitive skin.

Step 5: Move on to Next Gap

Start the next bead from the place you left off and repeat the steps. Don’t try to apply beads over the whole area at once, for the silicon caulk starts to harden quickly.

Keep an extra tube of silicon caulk around the house for the unexpected things that pop up needing a seal. Silicon caulk is very versatile, so being familiar with its many applications and how to use it is knowledge worth having.