Can You Use Flex Seal To Waterproof A Basement?

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Basements are vulnerable to water problems. If you have water leaking inside, you might not be able to do your usual activities. It's crucial to find suitable materials that keep your basement waterproof. That is why we have researched if you can use Flex Seal for your basement.

Flex Seal is a trusted product for waterproofing basements. You can use Flex Seal to prevent water from coming inside the basement. There is a wide range of products in the Flex Seal line to tackle water leaking. The product works by coating, sealing, and protecting the cracks where water can pass through. Also, Flex Seal will work with most types of surfaces, even concrete.

You can use Flex Seal with other waterproofing techniques like indoor drains or epoxy paint for best results. It will help you prevent water damage by following the instructions when applying the sealant. Read further to learn how you can waterproof your basement with Flex Seal.

A large basement gets a renovation with man's hand holding flex seal, Can You Use Flex Seal To Waterproof A Basement?

Is Flex Seal Good For Waterproofing?

Flex Seal is a liquid rubber sealant. You apply the product using a thick liquid on cracks or holes on the surfaces you need to seal. When it dries, it creates a watertight and flexible barrier due to its rubberized coating.

Flex Seal stops leaks fast once dry. It seals out the air and moisture in the areas applied. The sealant will not sag or drip when it is summer and won't crack in winter.

The brand offers a range of products for waterproofing the basement. Flex Seal can either be in liquid, spray, shot, glue, paste, or tape form. Aside from the foundations of your basement, you can use this sealant for windows, doors, and vents. But it won't work on specific plastic, vinyl, or rubber surfaces.

As long as you follow the directions to apply Flex Seal, your basement can stay waterproof for a long time.

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Can You Use Flex Seal On Wet Concrete?

You can use Flex Seal on various kinds of surfaces, including concrete. But when concrete is wet, it might not work as expected. Wet areas reduce the effectiveness of the sealant. You should apply the sealant on a dry and clean surface free from any oil or grease.

When you try to apply it when it's raining, it might get washed away. If possible, you should apply Flex Seal before rain, snow, or hail.

How Long Does Flex Seal Last On Concrete?

Most basements have concrete foundations which are susceptible to cracking and water seepage. If you apply Flex Seal on concrete, it will last up to 2 years.

The length of time it adheres to concrete depends on the basement temperatures and conditions. The ideal temperature of the surface should be around 32 to 120 °Fahrenheit.

Follow the tips below to maintain the Flex Seal on concrete for longer.

  • When preparing to apply the sealant, you can use a cleaning solution to get rid of accumulated dirt. Rinse and completely dry the surface.
  • Do not dilute the Flex Seal with any solvent or water.
  • Mix the concrete patch with the sealant until you get a thin consistency.
  • You can apply extra coatings as needed to cover all areas. A gallon of Flex Seal covers 150 square feet.
  • Smoothen out any excess of the paste to get an even finish. You have at most 10 minutes to readjust the sealant.
  • Wait at least 24 hours for the sealant to dry completely.

Is Flex Seal Good For Concrete Cracks?

For concrete repair specialists, they recommend using Flex Seal to repair concrete cracks. The sealant is a strong adhesive that bonds well with concrete. It remains waterproof and flexible seal to adapt with the movements of the concrete.

The elastic polymer in Flex Seal allows the product to resist harsh and changing environments. There are no ingredients like asbestos, asphalt, or bitumen that will deteriorate as concrete ages.

Here are some benefits of Flex Seal for concrete cracks:

  • Fast and cheap option to repair cracks
  • It stops the cracking from getting wide and worse
  • Prevents delamination of surfaces
  • Inhibits growth of moss and insects in cracks
  • Help improve the appearance of the area
  • Easy painting and clean-up
  • Can reduce mold and mildew build-up

Don't hesitate to use Flex Seal to get tough protection against water in the basement.

How Thick Can You Apply Flex Seal?

It is up to you how thick you apply Flex Seal on the problem surface. It will take around 2 to 3 hours to dry to the touch and at least 24 hours to fully dry. But the thicker the layer, the longer it will take to cure.

For 1/2-inch thick Flex Seal, it will take around 8 to 9 days. You should apply layers of Flex Seal instead of one thick layer to facilitate drying.

If you think that you poured a thick layer of Flex Seal liquid, you can use mineral spirits before the sealant dries. You cannot use alcohol-based solvents when trying to remove the excess. If you choose Flex Seal spray, you don't need to thin it out.

What Are The Best Products To Waterproof Basement Walls?

Aside from Flex Seal, there are other options you can use for waterproofing the basement walls. The products you will use will depend on the severity of issues you want to fix. You must know the reasons for water intrusion before you can select the products to apply.

Listed below are some waterproofing products for basement walls:

  • You can fill the cracks with hydraulic QUIKRETE hydraulic water-stop cement.

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  • Use masonry or polyethylene caulk to avoid leaks coming from the basement windows and doors. You can use GE 100% silicone window and door caulk. It will also help to use covers for the window wells.

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  • Apply a masonry waterproofing product like Drylok.

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  • You can also coat the wall with waterproofing paint. Try using RadonSeal deep-penetrating concrete sealer to fight both water and radon in the basement.

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You can use a combination of these products to get more protection against water damage in the basement. It will also help to ask for advice from a professional for suitable waterproofing products and methods to use in the basement. 

In Closing

A large basement gets a renovation with man's hand holding flex seal, Can You Use Flex Seal To Waterproof A Basement?

Keeping a basement dry is tough. With Flex Seal, you can fix the cracks on foundations by creating a waterproof and flexible barrier. You can use Flex Seal on wet surfaces, but it is more effective to apply on dry areas. The sealant's strength also depends on the thickness of the application.

Clean and dry the concrete surface where you will apply the sealant. Flex Seal lasts up to 2 years on concrete. Although Flex Seal is already a good waterproofing product, you can select other products to meet your needs. In the end, you should prevent water from coming inside your basement so you can live comfortably.

You can read related articles about basements in these posts:

Can You Epoxy A Basement Floor?

Water Leaking Into The Basement After Heavy Rain – What To Do?

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