Flood Protection Paste

Removable waterproof paste seeps into cracks.

Option: 9oz Cartridge

The Flex Seal Family of Flood Protection Products are specifically designed to work TOGETHER to create multiple layers of super-strong, waterproof protection, and to be easily removed after floodwaters recede. They can help slow down or even stop water from entering structures.

Flood Protection Paste is the primary Flood Protection product and should be used as a base coat for your first layer of protection. It starts out as a thick paste that can be pushed deep into all types of openings and hard-to-reach areas. It dries to a strong, flexible, rubberized barrier. It seals out water, air, and moisture and remains completely flexible.

Available in a Cartridge and Wrapped Sleeves.

WARNING: California Proposition 65 Notice.

Flood Protection in a Cartridge

Features a has a precision nozzle that allows you to target specific areas that need to be sealed. Use on windows, doors, garage doors, and all types of seams, casings, thresholds, conduits, vents and ducts, keyholes, and more.

Flood Paste in a Wrapped Sleeve

Designed for use on larger areas, flat surfaces, or directly on top of our other Flood Protection products and is applied with a putty knife. Use on basement widows, pet doors, crawlspaces, seams, windowsills, foundation cracks, and more.

For complete instructions, visit flexsealproducts.com/flood.

No water penetration through 1/2 inch gaps at depths up to 3 feet, for 14 days. UL Verified. VerifyUL.com. V114667.

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.

Patent Pending for Products and Uses.


Depending on temperature, humidity and thickness of application, Flood Paste will dry to the touch in approximately 2-6 hours, and fully cure in approximately 24-48 hours. Allow product to fully cure before floodwaters arrive. Flood Paste begins to cure when exposed to the air. Remove any dried material and always use fresh material to seal an opening.



Flood Protection Cartridge (9oz): A 1/4" inch bead will cover approximately 21 linear feet.

Flood Protection Cartridge (28oz): A 1/4" inch bead will cover approximately 62 linear feet.

Wrapped Sleeve

The coverage one coat of the (3) 8.75oz individually wrapped sleeves of Flood Protection Paste, when applied 2 inches wide, is approximately 31 linear feet.

The coverage one coat of the (6) 8.75oz individually wrapped sleeves of Flood Protection Paste, when applied 2 inches wide, is approximately 62 linear feet.


Always follow state and local weather advisories and evacuation orders. Depending on age and type of construction, there may be areas that cannot be seen or sealed. Unsealed porous surfaces may seep water during extended underwater exposure. Our Flood Protection Products are NOT intended for flash floods, extreme winds or water pressure, to protect against flying or floating debris, or if there is structural damage to the building.


All of our Flood Protection products are Patent Pending for both products and uses.

Made in the USA with globally sourced materials.

Color of product is high-visibility yellow.

For more information on UL testing, click here.

How To Use Flood Protection Paste (Cartridge)

For instructions on how to seal doors, windows, electrical outlets and other areas around your home or business, visit: flexsealproducts.com/flood

Read entire label for directions and warnings before use.

• Protective gloves, clothing, andeyewear are recommended.

• Apply to the exterior of the structure.

• Area being sealed must be clean, dry, and free of grease, oil, and dirt.

• Unscrew nozzle, cut the nub on the cartridge, being careful not cut or damage threads.

• Screw nozzle back on cartridge and cut nozzle to the desired thickness of the bead.

• Place the cartridge into a caulking gun.

• Using a smooth motion, apply an even bead directly to the areas being sealed.

• Use your finger or tool to push the bead into the surface being sealed. (Gloves recommended)

• Apply additional coats after 2-6 hours or when dry to the touch.

• Additional coats should overlap and be wider than previous coats.

• Material can be tooled for approximately 10 to 15 minutes before curing begins.

• Allow approximately 24 to 48 hours to fully cure before floodwaters arrive.


Grab a small portion of material from an edge and pull away from the structure. Using a small pair of pliers may be necessary. If any residue is left on the surface, use a stiff nylon brush, paper towel or rag with denatured alcohol to clean the area.