How to Caulk Interior Windows

Energy conservation includes making your house more airtight. Most leakage occurs around the doors and windows. Oddly enough, your house must have a little breathing room to avoid excessive build up of condensation. To this end you want to slow down and minimize the air flow, not eliminate it completely. Sealing your doors and windows will still leave breathing room in the structure and is well within the skill set of a homeowner. Using the right tools and preparing your work area will make your job much easier and minimize the clean up required. Acrylic and latex materials are recommended because they are paintable when dry. Pure silicone materials are more flexible and have higher adhesion but they are not paintable.

Windows are the leading cause of drafts.
  1. Use the sponge and water bucket to clean the area around each window where the frame or trim meets the wall. A damp sponge will be effective and prevent water from running down the wall. It is important for all surfaces to be clean before you try to seal them. Keep the bucket and sponge handy for later.

  2. Cut the tip of the caulking tube at an angle to yield a hole no larger than 1/4 inch. A larger hole will just make a bigger mess. Place the tube into the caulking gun and gently press the trigger to get the material started in the tip. Wipe off any excess that leaks out.

  3. Start at a corner, pull the trigger slowly and move the tip along the joint evenly overlapping both surfaces. This will deposit a bead of caulk covering the joined surfaces. Use light pressure to insure that you fill the gap. Complete a bead of caulk around the entire perimeter of the window. Try not to leave gaps in the corners.

  4. Use your sponge with clean water to dress the beads. Rinse the sponge and squeeze it almost dry. Lightly drag it along the length of each bead using enough pressure to shape the bead to the joint and fill in any gaps. Pay particular attention to the corners. Repair any gaps and repeat the wiping process.


  • Do not use the squeeze tube type caulking because it is difficult to control and more expensive for the area covered..
  • If the gap is larger than 1/2 inch use expanding foam.
  • Siliconized caulk is not paintable.

About the Author

After attending Pasadena City College as a business major, Ron Sardisco spent 35 years studying small business and organizational behavior. More than 20 years as a banker, 10 years as a small business owner and five years as a business adviser fuel his passion for writing and mentoring others. An award-winning photographer, he was also a contributing columnist to the "Antelope Valley Press."