Exterior Caulking


Exterior caulk doesn’t get much attention, but it plays a critical role in helping to prevent air and water leaks. Its elastic nature keeps your windows and doorframes sealed when outside temperatures cause materials to shrink and expand. All that movement over time causes the caulk to separate, so it’s important to check it consistently and remove and reapply it when you need to. With regular maintenance, you’ll help keep your home cozy.

Care and Maintenance

Follow these care and maintenance suggestions for your home’s exterior caulking.

To Check Caulk

Check for separated and deteriorated caulk around the exterior of your home about one to two times a year. The following are typical places that need caulk:

  • Between the foundation and the siding.
  • Around window frames and door frames.
  • Around any object protruding from an exterior wall, such as vents, outlets, pipes, and faucets.
  • Around any object protruding from the roof, such as chimneys, vents, and skylights.
  • At the corners and angles between siding materials.

Use an elastomeric caulk to do any repairs.

Don’t use acrylic caulking over silicone caulking and vice versa. These two types of caulking do not bond properly with each other.

To Reapply Exterior Caulk

1. Remove the old caulk with a putty knife, scraper, or painter’s tool.

2. Clean and dry the area that needs re-caulking. Caulk won’t adhere correctly to a damp or dirty surface.

3. Apply the new caulk. Hold the caulking tube at a 45° angle from the surface and push, rather than pull, the tube to drive the caulk into the gap. Pushing helps to fill the gap completely without trapping any air bubbles.

4. Twist the caulking tube and pull it back to break the caulk bead.

5. Run your finger along the joint to smooth and compress the caulk.

If you’re using a caulking gun to apply the caulking, follow the directions on the tube to load and use the gun.

Don’t apply exterior caulk in cold weather. Caulk is best applied when the outdoor temperature is between 50°F and 70°F.

If Your Home Is Part of a Homeowners Association (HOA)

Check with your HOA regarding maintenance, and be familiar with all HOA documentation.