How To Seal Single Doors

Our video below will maximize your success when preparing for a flood using the Flex Seal Flood Protection line. Single doors 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.
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.
If the door you’re about to seal is your primary entry or exit, it’s important to remove all persons, pets, and essential items before sealing your last entry point. You will not be able to re-enter without breaking the seal of our Flood protection products.

Once your door is closed tight, you're ready to start sealing it. Apply a medium bead into the threshold and the bottom of the door, between the door and the door frame, and the bottom of the entire threshold (including screw holes) — making sure all sides and corners are completely sealed.

Once applied, use your finger or Flex Gap Filler Tool to push it in, and smooth the area being sealed. A common mistake is not pushing it in deep enough after application.
Apply Tape
To seal the keyhole, you'll need to use Flood Protection Tape. Cut a small square peel the backing, and place over keyhole.

Completely cover the Flood Tape with the Flood Paste. Smooth out the Flood Paste with your gloved finger, spreading the Flood Paste over Flood Tape edges.

Once all areas are sealed, you have to let it dry.
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 and Tape.

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

When applying our Flood Protection Liquid, use your brush and apply it directly on top of our Flood Protection Paste, making sure you overlap your final coat — this will help cover any pinholes or openings that you can't see.

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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