Common Concrete Sealer Problems and How to Deal With Them

Common Concrete Sealer Problems and How to Deal With Them

Throughout its lifetime, concrete can suffer various types of damage. Although concrete can be protected with concrete sealers, problems related to this can be a source of frustration for contractors.

When a concrete sealer doesn’t perform as expected, the issue could be caused by various factors such as overapplication or the buildup of multiple coats.

In this article, we'll talk about the top five common issues encountered by contractors when it comes to using concrete sealers.

Sealer bubbling

If the concrete sealer is overapplied, the surface will tend to bubble up and become trapped in the gas. This could be caused by the heavy product application that's involved in the project. During the application of the concrete sealer, outgassing should be free to move through the thin, wet film.

One coat of concrete sealer should be around 5 to 10 mils thick when wet. However, when it's dry, it should only be around 2 to 3 mils thick. This means that a credit card is around 120 mils thick, while a sheet of copy paper is around 10 mils thick.

If you overwork the concrete sealer, the air that's displaced through the surface will not be able to escape, and it will start to form bubbles in the concrete surface. To avoid this, apply two thin coats instead of one heavy coat.

Sometimes, a bubble can form in the concrete surface after a concrete sealer has been applied in hot weather. When this happens, the solvent will try to evaporate, and this will cause a buildup of pressure on the surface. To avoid this, it's important that the concrete is placed in the cool part of the day.

Solvent-based sealer turns milky, peels or flakes

Over time, the heavy coats of concrete sealer can lose their adhesion to the concrete surface, and this can lead to the formation of flakes. One of the most common factors that can affect the performance of a solvent-based concrete sealer is its whitening.

The first sign of this issue is when the concrete sealer is applied to a wet concrete surface. If this happens, it will not bond to the concrete surface, and it will float on the trapped film of water.

Another issue that can cause a lot of sealer blushing is the overly thick application. Over time, the heavy coats of concrete sealer will cause the moisture under it to get trapped. This will eventually cause the concrete to lose its adhesion to the surface, and this will lead to the formation of a refractive index. This will make the concrete look white to the human eye.

Follow the manufacturer's recommendations and follow the application rate and number of coats to avoid this issue. Also, if the previous coat has already worn away, you should not reseal the concrete. After the solvent wash, let the concrete dry completely.

Water-based sealer is milky or powdery

Sometimes, concrete sealer can also become white or powdery after the latex particles did not fuse properly before it dried. This can happen because the concrete did not have the necessary adhesion to the surface.

The process of drying water-based concrete sealer is quite complicated. It involves a process known as coalescence, which is caused by the water and the coalescing solvent. During this process, the water and the solvent evaporate, and the resulting acrylic particles will fuse together to form a film.

If the humidity or temperature conditions are too high or too low, the coalescing agent will evaporate before the concrete's water. This can cause the concrete to become white or powdery. To avoid this issue, it's important to identify the necessary conditions for the successful application.

Before the concrete can be completely dried, it's important that the surface is cleaned and scrubbed. This can help prevent loose debris from forming on the concrete.

After the concrete has been thoroughly cleaned and scrubbed, it's important that the remaining product is brought back to the surface. If the previous coat did not provide the desired seal and gloss, then a light coat of concrete sealer should be applied. Usually, concrete curing and sealing solutions last for around one to three years. However, due to the wear and tear of the product, it's important to keep a close eye on it.

Follow the safety precautions and instructions outlined in the product data sheet and safety data sheet when working with solvents.

Wear and tear stains the sealer

Leaves can also cause stains on concrete when they're left on the surface for a long time.Prolonged exposure to debris can affect the properties of concrete sealer.

It's also not uncommon for concrete sealant to become stained due to general wear and tear. This issue can occur because of the exposure to debris, oil, and tire treads. Most concrete sealers are made with acrylic polymers, which do not provide the same chemical resistance and stain resistance as other types of products.

An epoxy or urethane coating system can help improve the durability and stain resistance of concrete sealant. It's also important to note that the coating should be appropriate for exterior use.

Concrete is dark and/or blotchy after sealer application

Film-forming concrete sealers can also look blotchy after they've dried due to various factors. Most acrylic sealers will darken the concrete and leave a glossy appearance, which tends to give it a "wet" feel. Since each concrete surface has its own unique characteristics, it's difficult to predict the color of the concrete after the application of concrete sealant. Certain factors such as the mix design, the use of chemical admixtures, and porosity can affect the surface's appearance.

A film-forming concrete sealer can also help deepen the concrete's true color and highlight the various inconsistencies in its surface texture. It's important to note that this type of product can bring out the grain in the concrete, just like a varnish does on wood. If you're worried about the effect of the sealant on the concrete's appearance, you can perform a small test application to ensure that the result is acceptable.

If you are looking for an ideal sealer for your next project, get in touch with us and we can assess what the best fit for your project would be. There are a wide variety of sealers that accomplish different objectives. Lets connect, we would love to help.

Written by Ryan Orser