Is Spray Paint Waterproof? (Different Types)

Spray paint is used for its beauty and easy application. But for the finish to last long, it must also thrive in wet conditions. So is spray paint waterproof?

Generally, spray paint isn’t waterproof. But, there are some types of it with additives that make its coating water-resistant and in some cases, waterproof. These are usually outdoor spray paints or sealants.

For instance, spray exterior enamel has impressive water-resistant qualities that make it thrive when exposed to moisture or rainfall. Also, spray sealants, such as spray polyurethane, are water-resistant. These sealants are sprayed on finishes to protect the finish from moisture.

To know if the sprayed finish is waterproof, you should check the information inscribed on the container. 

Waterproof vs Non-Waterproof Spray Paints

What Makes Spray Paint Waterproof?

Spray paints with water-resistant or waterproof qualities have a glossy top coat that prevents water from penetrating their coating. The glossy top coat is what makes the coating waterproof or water-resistant.

The additives in the coating and the sealant also make it waterproof. Spray paints that have plastic additives in their paint formula are water-resistant. The plastic additives when dry prevent water to get into the finish.

On the other hand, those that don’t have a glossy top aren’t waterproof. Non-waterproof spray paints usually have a textured finish and are made for indoor use.

However, if the spray paint isn’t waterproof, you can make it waterproof by sealing it with a waterproof sealant such as wax or lacquer. These sealants have the paint particles tightly packed and strengthened to prevent moisture from penetrating the material.

How To Know If Spray Paint is Waterproof?

How To Tell If Spray Paint Is Waterproof?

Check the paint container to know if the finish is waterproof. The container will indicate if the paint is waterproof or not. If there is no indication or inscription, the sprayer isn’t waterproof. And as such, it shouldn’t be used on surfaces or materials that will see moisture constantly.

You can also know if the sprayer is waterproof or not by checking the type of finish you get once it dries. If the finish is glossy, there is a high chance that it is water-resistant.

You can also tell by testing the paint. When the spray paint is dry, add a few drops of water to the finish and leave it for a few minutes. After about 10 to 15 minutes, check the spot.

If the surface doesn’t seem wet and you can still see the water you applied to it, the finish is waterproof. If the water has soaked into the finish, it isn’t waterproof.

Also, if the water appears tinted, the colorant of the finish has been dissolved by the water. This wouldn’t have happened if the finish was waterproof.

Does Rain Wash Off Spray Paint?

Does Rain Affect Spray Paint

Rain only affects normal and indoor spray paints. Rainfall doesn’t affect the exterior spray paint unless the coating isn’t fully cured before being subjected to rainfall or washing. The effects of rainfall become limited if the coating is allowed to cure fully.

On average, spray paint should fully cure for at least 3 days before rainfall. But, for the best results, let it dry for about 7 days before exposing it to rain or constant water. 

Indoor and decorative spray paints shouldn’t be exposed to rainfall regardless of how long the paint is left to cure. They aren’t built to withstand intense moisture or rainfall. If exposed to rainfall, the paint will be washed off.

But you can make the indoor spray paint water-resistant by sealing it with a water-resistant sealant like exterior polyurethane. This will prevent rainfall from washing off the coating.

Exterior spray paints can withstand rainfall and other weathering effects due to the additives and gloss in the paint formula. But you can also seal it to make the finish withstand heavy rainfall better.

Can You Wash off Spray Paint With Water?

Spray paints come off with water if the coating is still wet. This is because wet coatings are water-soluble, meaning they will dissolve in water. However, if the coating has dried, water won’t affect it. 

Spray paint will still come off if exposed to high moisture content or water for extended periods. However, this goes for indoor types.

Once the paint has cured, exterior types don’t come off in the water. To remove cured exterior spray paint, you need an alcohol-based solvent like isopropyl alcohol. This is because the coating will no longer be water-soluble. As a result, it will not wash off or come off with just water.

Types That Are Waterproof:

Acrylic Spray Paint

Acrylic spray paint is water-resistant and not waterproof. When dry it produces a water-resistant sheen or gloss that seals the finish and prevents most of the water from penetrating. 

If exposed to high moisture content or constant rainfall, it will begin to soften and gradually allow water to pass through. This is why the term “water-resistant” is used instead of “waterproof”. For paint to be waterproof, the finish has to withstand moisture completely but most paints can’t do this.

However, the exterior acrylic spray has impressive water-resistant qualities that are as close to being waterproof as you can get. The paint can cope with rainfall due to its flexible and impermeable top layer. So, for surfaces that will see rainfall or moisture regularly, you should use it.

You can also improve its water-resistant qualities by sealing it with waterproof sealants.

Rust-Oleum Spray Paint

Rust-oleum spray paint is waterproof. When dry it forms a protective barrier that prevents water or oils from penetrating the finish. This is one of a few spray paints that is fully waterproof.

The protective barrier that it forms is strong enough to block moisture content for over 10 years. This is because of the chemicals and additives in the paint coating. It is particularly designed to prevent water from damaging metal.

This spray paint is commonly used on metal and its main feature is that it prevents rust by blocking out moisture. So if used, you are guaranteed a waterproof coating on the surface.

Krylon Spray Paint

Krylon spray paint is waterproof as it is specially made for outdoor surfaces. It comes with a formula that gives durability to outdoor surfaces. You can use it for wood, metal, plastic, and fabric. 

The Krylon spray paint takes less than 1 hour to dry. Once it dries it can withstand rain and water. So, it’s a great choice to waterproof outdoor objects. 

Things To Know

Is it Permanent?

No, spray paint isn’t permanent. After a few years, it will wash off from surfaces. But, this usually takes more than 10 years.

The time it takes for it to wash off depends on the type of paint and where the painted object is located. For example, spray-painted indoor objects tend to last longer than outdoor objects.

You don’t have to seal waterproof spray paint. But, you should seal a non-waterproof and water-resistant finish. The sealer will give the finish waterproofing features, and protect it from moisture and water.

Final Words

In summary, spray paint isn’t waterproof. But, some specific brands have water-resistant and, in some cases, waterproof qualities. Always check the information on the container to know if it is waterproof or not.

Even if the paint is advertised as waterproof, chances are it is water-resistant. To improve the water-resistant qualities of the finish, you can seal it with a glossy or any other water-resistant top coat.

Tony Adams
Tony Adams

Tony is a professional painter and an author of DIY Geeks. Tony has completed over 1,000 painting projects for his clients. It's safe to say he knows what he Is talking about,

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