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How to Replace Caulking in a Swimming Pool Expansion Joint

By J. Johnson ; Updated September 21, 2017
Basic maintenance helps your swimming pool last.
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A swimming pool is not something that you can simply have on your property and enjoy each summer without thinking much about it. On the contrary, a swimming pool requires many hours of regular maintenance, as well as some side projects that come up when things go wrong. One such side project might be replacing crumbling or worn-out caulking between the expansion joints that are found outside of the swimming pool, between the coping on the top edges of your pool and the deck or other surface outside of the pool.

Step 1

Scrape out the old caulk in the joint carefully using a putty knife.

Step 2

Wipe any moisture out of the area and let it dry for a few more hours in the sun.

Step 3

Tape off the area so only the expansion joint is visible. Lay a strip of backer rod foam in the space before caulking.

Step 4

Apply an elastomeric sealant caulk that’s intended for outdoor use into the expansion joint, using a caulking gun to lay a consistent bead of caulk that is 1/2 inch in diameter.

Step 5

Smooth over the surface of the caulk with a rubber float.

Step 6

Pull off the tape before the caulk sets. Allow it to dry for the manufacturer-recommended length of time before getting it wet.


Things You Will Need

  • Rags
  • Putty knife
  • Tape
  • Backer rod foam
  • Caulking gun
  • Elastomeric sealant caulk
  • Rubber float

About the Author


J. Johnson has been completing freelance writing work since September 2009. Her work includes writing website content and small client projects. Johnson holds a degree in English from North Carolina State University.