How To Seal Conduits

Our video below will maximize your success when preparing for a flood using the Flex Seal Flood Protection line. Conduits can vary in shape and design, so it is important to seal any area where water may enter.
Always follow evacuation orders. Heed all directions from local government and emergency management officials. Watch our introductory video before starting.
Products Used:
Flood Protection Paste (Cartridge)
Flood Protection Liquid or Spray
Tools Used:
• Caulk Gun
• Flex Gap Filler Tool
• Paint Brush
• Putty Knife
• Protective Gloves
• Eyewear
Flood Paste in a Cartridge is the base coat for your first layer of protection. Use a gloved finger, Flex Gap Filler tool, or similar tool to push into all seams and openings to help create a watertight seal. Always be cautious of any sharp objects that may cause injury.
Apply Paste
Apply an even layer of Flood Paste around the pipe where it meets the wall, filling in any voids. Use your gloved finger, Flex Gap Filler tool or other similar tool to firmly push the Flood Paste deep into the gap and smooth it out.

NOTE: The valve itself does not need to be sealed, as it is already watertight.
Additional Layers
If you applied Flood Protection Paste in thin, even layers, you should expect it to be dry to the touch in two to six hours. Next, we recommend applying additional coats of our Flood Protection Paste as needed.

Follow the same application process as the first layer, but each individual coat that you apply should be wider and overlap the previous layer of Flood Protection Paste.

Once the conduit has been sealed and is completely dry, and you already have multiple layers of Flood Protection Paste, we recommend using our Flood Protection Spray or Flood Protection Liquid as an additional layer of protection.

If using the Flood Spray, apply a light coat using an even sweeping motion from 8” to 12” from the surface. If using the Flood Liquid, brush a generous amount over the entire area. Be sure you’re covering the opening and the area where the vent duct meets the wall. Using the Flood Spray or Flood Liquid will help seal any small openings or pinholes that may have been missed.

Remember you want to make sure all the flood protection products are fully cured before a flood arrives.

For additional help, click on one of our how-to options below, or call us at:
833-4-A-FLOOD (833-423-5663).

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We’re proud to say that when used in combination, and as directed, our Flood Protection Products have been independently verified by UL Solutions to hold back 3ft of water for 14 days on gaps up to ½ inch. Tested in laboratory settings.
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Flood Protection Products Support
‍Our dedicated Flood Protection Product support is here when you need it. Whether you have questions about our products, or need help ordering, our experts are ready to help.

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