Flex Seal Liquid is optimal for sealing, repairing, and weatherizing concrete. It works by sealing out air, water, and moisture and is mildew, chemical, and UV resistant. You can either brush, roll, dip or pour the liquid directly onto the concrete surface.
You can use concrete caulk on both vertical or horizontal cracks. Our top pick is Sikaflex Pro Select Self-Leveling Sealant. Self-leveling caulks flatten out as they dry, so you don't have to smooth them out yourself.
FLEX SEAL WHITE FLEX PASTE, 1LBFlex Paste is a thick rubberized paste that clings to the surface and instantly seals large gaps, cracks and holes. Once dry, Flex Paste turns into a strong, flexible, watertight, rubberized coating that seals out air and water.
New Flex Paste™ can be used on multiple surfaces, like wood, tile, metal, concrete, PVC, glass and more. What Flex Paste projects and repairs are on your radar? Get inspired today by watching our new commercial!
Flex Seal Liquid is a helpful resource for fixing driveway damage. The product can be easily poured into cracks and crevices for repair. It's important to note that we do not recommend sealing large areas that receive a lot of foot traffic because the liquid can become slippery when wet.
What Does Flex Seal Spray Not Work On? We do not recommend using Flex Seal on foam. Some foams may react poorly with Flex Seal, and may warp or dissolve.
If you have a lot of cracks, you may prefer to use dry concrete mix or concrete patching compound instead. For big or deep cracks, use a concrete mix or patching compound that contains gravel. Put the mix (or compound) in a large bucket and add water as directed on the label.
Epoxy and Polyurethane
Sealing and repairing cracks in a basement foundation helps prevent water leaks, helps keep soil gasses such as radon from entering (although radon can enter through means other than cracks), and keep the basement, crawlspace, and living area of the home healthier with better air quality.
Break away any deteriorating concrete and remove loose material with a brush. Cut the tip of the nozzle on an angle with a utility knife to match the width of the crack and load into a standard caulk gun. NOTE: for large cracks over 1/2 inch deep, a backer rod should be placed in the crack before applying the sealant.
Water can get into the joints, freeze and then expand, making the cracks even larger. Gaps against a house can direct water against the foundation, leading to more problems. Once a year, go around your home and fill these gaps and joints with urethane caulk (or polyurethane caulk) to prevent problems.
Flex Seal will last years when correctly applied. If you notice cracking or peeling, clean the area and apply a new coat to enjoy more watertight sealing.
Can Sealing Prevent Cracks on Concrete Surfaces? Concrete sealing can stop most types of concrete fractures. This fact is especially true if the crack is a result of poor-quality work in the concrete mix or site preparation. However, sealing can prevent future damage that may start from the top layer of the concrete.
A heavy-duty product like Red Devil's Pre-Mixed Concrete Patch is the way to go to fill large cracks and breaks. The 1-quart tub of patch is ready to go as soon as the lid is off, and it won't shrink or crack as it dries. Suitable for repairing concrete, masonry, brick, or block, it works both indoors and outdoors.
Polyurethane polymer: Using a high-viscosity polyurethane polymer is one of the best ways of sealing basement wall cracks. This is stronger and more durable than an epoxy, and it can be applied even if the wall is wet. The polymer can expand and contract with the wall, so you don't have to worry about further cracks.
For a bond strength that beats any standard repair concrete, the Damtite vinyl concrete patch is the best it gets. It is a self-bonding vinyl concrete that can be used on most concrete cracks, is able to build up the corner of steps, and will bond other materials such as tile and stone.
Remember to cut your Flex Tape larger than the area of the leak. You do not need to drain the pool prior to applying it. Flex Tape is a temporary, emergency repair and is not meant to be a permanent fix.
A: YES, Flex Paste can be applied on dry or wet surfaces and even underwater. It won't dissolve or wash away and even dries underwater.
A: Dry time depends on the temperature, humidity, and thickness of the coating. Flex Seal will usually dry to the touch within 2 to 3 hours and fully cure in 24 hours. It will get stronger over time.
According to HomeAdvisor, a driveway repair professional will charge as little as $300 to fix minor concrete driveway cracks, but most homeowners can do the job on their own with a rubber or synthetic crack filler. This costs about $0.10 to $0.15 per linear foot—but watch out if cracks are larger than 1/8 of an inch.
Brick: For sealing gaps in brick, a silicone caulk such as DOWSIL 758 Silicone Weather Barrier Sealant is a great choice. It's waterproof and can withstand extreme temperatures, making it ideal for use around windows, doors, and other penetrations.
For use on Driveways, Parking Lots, Streets, Highways, and Airport Runways. Flex-A-Fill® is a hot-applied polymer modified asphalt sealant used to seal cracks in asphalt concrete or Portland cement concrete pavements.