How to Add More Spray Foam to Kayaks

Many touring kayaks, or kayaks with storage bulkheads, use expandable spray foam sealant. This foam is sprayed into the small nooks and crannies in the kayak and expands to seal the air pockets as well as add extra buoyancy. When the foam is still wet, it is moldable, so it can be shaped to the particular area. If you have a need to add extra foam to the existing foam in the kayak, it is possible to add more over the foam already in the kayak.

Things You'll Need

  • Expandable spray foam
  • Rubber work gloves
  • Eye goggles
  • Putty knife
  • Paint scraper
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Instructions

    • 1

      Set the kayak up on a flat work area and make sure the area where the foam is applied is totally dry and free of grit and grime. Shine a flashlight into the foam area and see if there are gaps in the seams along the kayak hull by looking for direct light beaming through. Mark these areas with a marker.

    • 2

      Spray approximately 1/3 of the amount of foam you think you need. Most foams will expand up to three times the size of the foam when it leaves the canister. Once the foam is in the location, begin using the putty knife or scraper to mold it into the shape needed. For example, if you apply the foam into the nose of the boat, use the putty knife to mold it up and directly into the areas where the are gaps in the seam. Scrape away any excess foam to prevent it from hardening and expanding where you do not want it.

    • 3

      Let the foam harden and then cut away any portions which dissatisfy you. Shine the light back into the area and make sure the foam has sealed the gaps.

    • 4

      Use the foam to make custom leg and knee braces by applying the foam onto the underside of the combing and then sitting in the cockpit. Press your knees and legs up toward the foam and imprint your knee shape into the foam. Let the foam harden.