How to Prep Walls for Drylok

Drylok is a thick paint designed to prevent water from seeping though a block wall and into a basement.

Protecting your basement from water will elongate the life of your house.Protecting your basement from water will elongate the life of your house.
You apply Drylok just as you would latex paint. However before you can apply the Drylok to the wall, you must prep the surface. However, the preparation process is unlike painting a plaster of sheetrock wall. If you do not properly prepare the wall for the Drylok paint, you can expect the Drylok to fail and water to get into your basement.

Sweep the wall to remove any dust build-up and loose debris. Use a push broom, dust broom or bristle brush.

Remove any loose or peeling paint from the wall with a wire bristle brush. Scrape across the surface to break the paint off. If the wall is brick, scrape across the entire surface of the wall to remove any loose brick that has decayed.

Scrub the wall with hot soapy water mixed with a mildew cleaner. You can use a nylon bristle brush to scrub the wall. Once scrubbed, allow time for the wall to dry.

Fill in any vertical cracks in the wall that are no less than ¼-inch thick with a polyurethane sealing caulk. If you have vertical cracks wider than ¼-inch or you have horizontal cracks, consult a structural engineer before continuing to ensure the foundation does not require major repairs. If given approval by the engineer, fill in the remaining cracks with the polyurethane caulk.

Place a dehumidifier into the basement and reduce the humidity to a range between 50 and 60 percent humidity.

Things You Will Need

  • Broom
  • Bucket
  • Metal bristle brush
  • Nylon bristle brush
  • Mildew cleaner
  • Dehumidifier