How To Seal French & Double Doors

Our video below will maximize your success when preparing for a flood using the Flex Seal Flood Protection line. French and double 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.
Apply Paste (Cartridge)
Apply Flood Paste (cartridge) directly into the gap between the threshold and the bottom of the doors, between the doors, around the lock sets or door handles, and all seams. Also where single panes of glass meet the door and/or where multiple panes meet the mullions. Use gloved finger or Flex Gap Filler tool to push Flood Paste into seams and smooth out.

Apply Flood Paste along the front, bottom, sides, and corners of the threshold, including screw holes. Push the Flood Paste in and smooth it out with gloved finger or Flex Gap Filler tool.

Apply Flood Paste along where the doorframe meets the casing as well as where the casing meets the exterior wall. Push the Flood Paste in and smooth it out with a gloved finger or Flex Gap Filler tool.

Cut a small square of Flood TAPE, peel the backing, and place over keyhole, pressing firmly. Next, completely cover with Flood Paste and smooth out with gloved finger or other tool.
Apply Tape
Cut the Flood Tape to size. Remove the backing only a few inches and press the exposed adhesive side to the top of the area being sealed. Continue to pull off the backing, pressing the Flood Tape firmly with a gloved hand or squeegee to smooth out any creases or wrinkles.

Do not apply Flood Tape around corners, contoured surfaces, or irregular shapes, as they can create air pockets and allow water to enter.
Apply Paste (Sleeve)
Using a putty knife, remove the Flood Paste (Sleeve) from provided tray and apply an even coat on top of the Flood Tape, covering the edges (excluding keyhole) with each coat being wider and overlapping the previous one.
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 and Tape, making sure you overlap your final coat, this will help cover any pinholes or openings that you can't see. Don't forget the seal around the door handle and lock.

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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