Water Based Concrete Sealer

  • June 12, 2020
  • / By Dale Keese
water based concrete sealer

Water-based sealers are high-performance sealers with a low sheen and are generally low in VOC. The polymer particles are typically dispersed in water in a water-based sealer and when the water-based sealer is applied to the concrete surface, the polymer particles get closer when the water evaporates. As the water continues to evaporate, the particles get deformed and bond together, forming a clear and continuous coating.

Our pick for the best water based concrete sealer is the Foundation Armor SX5000WB Concrete Sealer due to it's breathable high solid content formula that lasts up to 10 years. It penetrates deeply protecting the concrete from damage while leaving a natural, unsealed appearance.

Click here to see our review.
Armor SX5000 Water-Based Concrete Sealer

The formulation of water-based sealers allow easy application and they are quick drying with excellent adhesion to the surface and also offer good general protection for the concrete surface. When they are applied to the concrete surface, water-based sealers turn milky white, as the polymer particles scatter visible light differently compared to the water in which the particles are dispersed, but the surface turns clear on drying.

Water-based concrete sealers do not darken the concrete surface like solvent-based sealers and so, the surface looks more natural. These sealers generally enhance the color of the surface moderately and provide a low-gloss, matte finish. However, water-based sealers do not offer the same levels of shine and gloss that is offered by solvent-based concrete sealers.

Facade with Decorative Concrete Flooring

Some of the advantages of using water-based concrete sealers are that they are not inflammable, they do not release hazardous vapors or strong odors of solvent sealers, and they are environment-friendly. Once the application is complete, the clean-up is very easy and quick. Water-based concrete sealers are generally safer for use indoors, especially when you have people, kids, and pets around.

Overall, water-based sealers are a good choice if you are looking for a high-performance, low-VOC concrete sealer that is easy to work with and is very durable.

  • Decorative concrete surfaces
  • Indoor concrete surfaces such as floors and countertops
  • Outdoor concrete surfaces

Application

Water-based sealers are much easier to apply and can be sprayed using a plastic garden sprayer, a paint roller, airless sprayer, synthetic closed-loop mop, or synthetic fiber pad to apply the sealer. Water-based sealers dry quickly and in warm weather, they will not flash dry.

First, prepare the concrete surface by sweeping or vacuuming it to remove the dust. Use a degreaser to remove dirt, oil or grease. Rinse the surface with clean water and allow it to dry. The water-based sealer should be applied to a dry surface. If the concrete is new, then allow it to dry for 4 weeks in summer and 6 weeks in winter. Usually, concrete surfaces do not require to be primed; however, if the surface is very porous, then you may need to use many coats of the sealer to get an even finish.

Using a paint roller, apply the water-based sealer in a thin coat like you apply paint. Let the sealer dry completely including the corners and any cracks before applying the next coat. Usually, the sealer will dry to the touch in around 1-2 hours. Do not apply the sealer unless the humidity is less than 65% and do not allow any moisture on the sealer for at least 12 hours.

Once you have applied the final coat of the sealer, let it cure for 24–48 hours before you let any traffic on it or apply wax. In warm weather, the sealer will dry completely in around 7-10 days and in cooler weather it will take around 14 days to dry completely.

If you are applying more than one coat, let the first coat dry completely before applying the next one. Ensure that when you are applying the water-based concrete sealer, the humidity is 65% or less and do not let moisture on the surface for a minimum of 12 hours. It is a good idea to apply a coat of wax on the sealer; however, this should be done only 24 to 48 hours after the water-based sealer coats completely cure.

Frequently Asked Questions

What is the difference between concrete sealer and waterproofer?

The main difference between a concrete sealer and waterproofer is that concrete sealers form a protective layer over the concrete surface, while a waterproofer penetrates into the surface and fills the gaps.

Concrete sealers are available in 4 types—penetrating, acrylic, epoxy and polyurethane. Depending on the location of the concrete and the kind of substances the concrete comes in contact with, each type of sealer has a specific use. For instance, an acrylic sealer is breathable and repels water, letting the moisture trapped below the sealer to escape, making it ideal for concrete surfaces that are exposed to the elements. On the other hand, polyurethane sealers offer a thick layer of protection for areas having high traffic, but it does not let the trapped moisture to escape.

Waterproofing helps to fill up cracks in different types of surfaces. Waterproofing compounds penetrate the surfaces and bond with the material, helping to close leaks. Waterproofers are more durable compared to sealers and they prevent water from flowing through the surfaces on which they are applied. They also help to block radon gas from escaping from the ground and also prevent water vapor from accumulating.

How much water based sealer will I need?

Water-based sealers usually go on very thin, which means that from 1 gallon of water-based sealer, you will get more coverage compared to a solvent-based sealer. With solvent-based sealers, you will get a coverage of around 800 sq. ft. per 5 gallons approximately, while a water-based sealer will give you a coverage of around 2,000 sq. ft per 5 gallons for 2 coats.

Can you paint over a water based concrete sealer?

You cannot paint over water-based concrete sealer and expect the paint to adhere for long. There are no pores in the concrete for the paint to be absorbed into and adhere to the concrete surface as the pores have been filled with the sealer that you have applied already. If you have used a water-based sealer on a concrete surface, then you can apply a solvent-based sealer on this.

Can you fix cloudy water based concrete sealer?

There may be many reasons for why the water-based sealer looks cloudy or milky. This may be because the sealer application took place when the temperature of the ambient air or the concrete surface was too low (for water-based sealers, both the surface, as well as ambient temperatures must be above 50oF). The cloudy or milky appearance may also be caused because of water or condensation trapped under the water-based sealer.

To fix the issue, you must wait until the winter is over and you have warmer weather. First, try using a xylene bath i.e. soak the cloudy/milky area with a xylene solvent and back roll. If this doesn’t work, then you may need to strip off some of the sealer or all of it and re-seal the area.

How long does water based concrete sealer take to dry?

Once you have applied the final coat of the sealer, let it cure for 24–48 hours before you let any traffic on it or apply wax. In warm weather, the sealer will dry completely in around 7-10 days and in cooler weather it will take around 14 days to dry completely.

How long does water based sealer last on concrete?

Water-based sealers usually last around 1 to 3 years on concrete surfaces, while solvent-based sealers will last longer compared to water-based sealers.

Can water based concrete sealer be removed?

You can remove water-based sealers from concrete by using an industrial strength stripper. Apply a thick uniform layer of the stripper (around 1/16 inch to ⅛ inch) to the sealer to be removed using a squeegee rake, gauge rake or airless sprayer. Let the stripper work and do not scrape or brush the surface. Use a scraper to test if the sealer has softened. If not, wait for some more time and then recheck. 

If the concrete surface is outdoors, then cover with a plastic cloth to prolong the wet time of the stripper. Once the sealer is soft, remove it using a scraper, industrial vacuum or some other tool. If the sealer has not been removed completely, reapply the stripper and repeat the above process. After all the sealer has been removed, using a mop, scrub brush or power washer to remove the residue and then rinse the surface using a power washer. Let the surface completely dry before any other process.