A Guide to Waterproof Paint

Worker coating floor with self-leveling epoxy resin in industrial workshop

Waterproof paint is formulated to resist moisture and save your walls, floors, and other surfaces from costly repairs down the line. Not only does it ensure protection, but also looks amazing with its range of finishes and colors.

In this guide to waterproof paint, we delve deep into the several types, application do’s and don’ts, and other details to help you understand this smashing paint type better.

What Is Waterproof Paint?

As the name suggests, waterproof paint is formulated to block water penetration and provide a protective barrier against moisture. It has a combination of pigments, resins, and additives, which creates a tough, long-lasting, and water-repellent coating. 

Waterproof paint can either be entirely waterproof (is this even true? We’ll discuss this later) or water-resistant. It withstands exposure to water without peeling, cracking, or swelling. Waterproof paint also resists mold and mildew growth. 

This makes waterproofing paint an ideal choice for humid areas of your home or where the paint is likely to encounter more water exposure such as in kitchens, bathrooms, or basements. Such paints are also excellent for protecting exterior walls that are prone to dampness and water seepage. 

Types of Waterproof Paint

These common paints possess waterproofing qualities. 

Acrylic Paint

Acrylic waterproofing paints are water-based and known for their easy and smooth application. They adhere to a variety of surfaces, including wood, concrete, and metal. They have low volatile organic compounds (VOCs) and are safer for the environment than their counterparts. 

These paints are easy to apply and clean and are used for both indoor and outdoor applications. Because they’re elastic, they allow for expansion and contraction without splitting. You can seal wood, masonry, concrete blocks, poured concrete, stucco, clay tiles, and more. And acrylic paints come in matte, satin, and gloss finishes.

Read more about this paint type in our detailed acrylic paint guide

Polyurethane Paint

Polyurethane is a rubber-like, flexible coating that works on concrete, wood, and metal. This waterproof paint type is known for its UV resistance and excellent water-repelling qualities. 

Common applications of polyurethane-based waterproof coating include terraces, balconies, roofs, kitchens, patios, basements, bathrooms, and construction sites. They’re easy to apply, give a smooth and seamless finish, resist UV damage and corrosion, and offer exceptional durability. 

You may also find polyurethane coatings on concrete and cement surfaces, such as indoor and outdoor floors, because of their strong adhesion and high load-carrying capacity. Plus, these paints also stand up well against freezing temperatures and offer an aesthetic appearance.

Epoxy Paint

Commonly used on concrete surfaces, epoxy paints are known for their durability and resistance to abrasions and chemicals. This paint contains epoxy-based resin known as polyepoxides and is about five times thicker than an average floor paint.

Epoxy paints are highly durable, waterproof, long-lasting, and easy to clean. Epoxy paints are resistant to rust, chemicals, heat, acid, and of course a great deal of moisture.

Garage floors, decks, driveways, walkways, and other such surfaces look beautiful with an epoxy finish. Not to mention, it’s an excellent protective layer against automotive fluids, hot-tire pickup, and most household chemicals. 

Check out our epoxy paint guide for more information.

Acrolein Elasticized Paint

Acrolein elasticized paint is typically used on concrete surfaces. Acrolein is combined with acrylic paint to convert it into a waterproof coating. This coating will prevent mold, mildew, and other bacteria that are fond of moisture. 

Take extra care when handling this paint since the high toxicity can affect the skin, lungs, and throat. Apart from concrete, acrolein elasticized paint is used on cinder block and stone surfaces. 

Masonry Paint

Masonry paint is made from latex and ceramic materials and is used for stones, cement, bricks, cinder/concrete blocks, etc. This paint makes surfaces waterproof, durable, dirt-resistant, and long-lasting. Masonry paint is environmentally friendly and possesses anti-fungal and anti-aging properties. 

Masonry paint is perfect for outdoor applications because it is UV-resistant and will keep your walls safe from cracking, flaking, and peeling with time. It’s also super easy to clean; all you need is soap and water. 

What Makes Paint Waterproof? How Does it Work?

The secret to how waterproof paint protects surfaces from moisture is in its composition. Most waterproof paints consist of these key ingredients:

  • Resins: Resins are binders in the paint. They bind the paint pigment particles together to form a cohesive film. Waterproof paints have specialized resins that enhance water resistance and create a tough, long-lasting coat.
  • Additives: Several different types of additives are added to waterproof paints to improve their performance as a protective shield. These additives may include thickeners to enhance the consistency, biocides to prevent mold and mildew growth, and UV absorbers to protect against harmful sun rays. 
  • Pigments: Pigments provide the color and opacity of the paint. Pigments don’t make paint waterproof in any way, but they make it aesthetically pleasing. 

How Do Waterproof Paints Work?

The measure of waterproof paint is its ability to form a water-repellent barrier on a surface. This barrier is created by a combination of the following factors:

  • Hydrophobic Materials: Waterproof paint has hydrophobic materials that repel water naturally. These materials help to form a microscopically smooth barrier that prevents water or moisture from adhering to the paint. Instead, you see water droplets bead up and trickle down the surface without any absorption. 
  • Polymerization: Resins in waterproof paint undergo a chemical reaction after application, known as polymerization, and form a deeply bonded, continuous film. This film acts as a physical barrier and prevents water from entering. 
  • Micropores and Microcracks: Waterproof paints contain small microcracks and micropores that you might not be able to see. Despite the strong film formation, these tiny cracks allow the paint to breathe and permit the trapped moisture to escape. This helps the paint maintain its water resistance. 

How Effective Is Waterproof Paint?

Waterproofing paint is an affordable and easy solution to tackle most of the water-related issues in your home. Plus, it’s easy to apply as a DIY project. But is waterproof paint as effective as it’s marketed? 

The fact is waterproof paints don’t eliminate the source of moisture and only create a barrier to hold it back. Commonly used basement materials such as concrete are porous, which means water vapors penetrate through them. These vapors have minerals in them that eventually form white, flaky powder buildups called efflorescence. 

There’s a possibility that this buildup may occur behind waterproof paint coatings, too. If it does, it will exert pressure that will eventually cause the paint to flake off, peel, or blister. 

Our verdict: For porous surfaces, waterproof paint is only a temporary solution. You can expect waterproofing to last anywhere from six months to two years in a wet basement before it starts to show damage. The effectiveness of your waterproof coating also depends on the quality of the prep work because the coat needs to have a solid bond with the surface underneath to be effective. 

When To Use Waterproof Paint

Man painting a swimming pool in blue with a paint roller
Photo Credit: pepifoto / Canva Pro / License

Waterproof paint is perfect for a variety of settings that frequently get exposed to moisture and water. Here’s when and where you can utilize waterproof paint:

  • Kitchens and Bathrooms: Waterproof paint is ideal for spaces that encounter high levels of moisture and humidity such as kitchens and bathrooms. It seals the walls and ceilings and protects them from water damage, preventing problems like cracking, peeling, and mold growth down the line. 
  • Basements: Basements are prone to dampness and seepage. Waterproof paint on floors and walls of a basement will create a solid moisture barrier and safeguard against potential damage and leaks. 
  • Garage Floors: Garage floors often see a ton of water and chemicals and a waterproof coating can help prevent the damage such exposure can cause. It forms a protective barrier and prolongs the life of the concrete. 
  • Exterior House Surface: Waterproof paint can protect exterior walls, concrete sidings, and wood siding from harsh weather conditions, rain, and wind. 
  • Pools: Water features like pools and fountains need a protective layer of paint to prevent water from penetrating the structure and reduce the risk of leaks and cracks. 

When NOT To Use Waterproof Paint

Waterproof paint makes an effective barrier against moisture, but it’s also important to know its limitations. Understanding areas where your water-resistant coating falls short will help you make a regular maintenance schedule to ensure it lasts a long time.

It’s best not to use waterproof paint for:

  • Fixing Structural Issues: Waterproof paint is formulated to protect against water damage but won’t remedy any structural problems. Underlying issues in the structure can cause leaks and foundation cracks and should be addressed separately. 
  • Hiding Imperfections: Waterproofing paints won’t give the desired results if you apply them without properly preparing the surface. The surface should be dry, clean, and free from dirt and debris before application because if it isn’t, waterproof paint won’t adhere. Any cracks or damage also need to be properly repaired before painting. 
  • Painting Very Congested Spaces: Some waterproof paints emit a strong odor and are not safe for application in congested areas. You must ensure extra ventilation to ensure safety during paint application

How to Apply Waterproof Paint

Closeup of hand with paint brush painting building exterior wall
Photo Credit: Ja’Crispy / Canva Pro / License

Here’s a simple step-by-step guide to waterproof paint application:

Step 1: Check and Repair Faults

The first step is to inspect and eliminate any damage on the surface. These repairs might be as small as tiny surface cracks or as big as leaks and foundation damage from structural issues. Make sure you treat everything and patch holes before you apply and seal the surface with waterproof paint. 

Step 2: Prepare the Surface

Clean the surface to remove any dust, debris, peeling paint, or chalky residue. Dirt and debris do not allow the paint to stick properly to the surface. For some surfaces, you might also want to sand and prime before painting.

Step 3: Choose the Right Paint and Apply

As discussed earlier, there are different kinds of waterproof paint. Research which type will suit the surface and location you’re painting before you make the purchase. Then, use the right brush or roller to apply the waterproof paint evenly over the surface and allow adequate time for your first coat to dry. Check the paint box and follow the drying instructions and time.

Step 4: Apply a Second Coat

Once the first coat has completely dried, apply a second coat of paint. Make sure you give extra attention to any thin spots or missed areas from the first coat. 

Benefits and Drawbacks of Waterproof Paint

Let’s take a quick look at the pros and cons of waterproofing paint:

Benefits of waterproof paint

  • Prevents mold and mildew growth which not only damages your home but harms your health too.
  • Easy to clean as compared to regular paint. This is because it resists stains and you can simply wipe a stain away with a damp cloth if you spot one.
  • Highly durable and long-lasting due to specialized resins and water-repelling qualities. 
  • A variety of colors and finishes ensure that your well-protected walls still look aesthetically pleasing. You can pick the color and finish that matches and complements your home style and color themes.
  • Resists and mitigates serious water damage even if the barrier falls weak due to a structural issue. 
  • Super versatile, you can apply waterproof paint on various surfaces without worrying about it peeling or cracking later. This includes walls, floors, ceilings, and exterior surfaces. 

Disadvantages of waterproof paint

  • Need specialized application techniques that can sometimes make application a challenging process. 
  • Higher price tag than most regular paint types due to its higher production costs and specialized properties. Waterproof paints cost somewhere between $1 and $8 per square foot. 
  • May have a strong odor and need extra ventilation during application.
  • Is not a permanent solution if there is an underlying problem causing chronic water leaks or excess moisture. 

Waterproof Paint vs. Regular Paint

Waterproof PaintTraditional Paint
Requires more surface prepSurface prep is not as extensive
Preparation of substrate is intrusivePreparation of substrate is less intrusive
End goal is to protect, mostly used as a sealerIntended purpose is mostly cosmetic appeal
May increase the cost by added prep expenses covering sealing, crack routing, and epoxy injection prior to paintingPretty affordable for most paint types
Creates a water barrierResists water
Suitable for painting and sealing bathroom, kitchen, basement walls, and exterior and interior wallsSuitable for a variety of surfaces depending on whether it’s water-based or oil-based
Formulated with special hydrophobic ingredients and waterproofing additivesThe formulation contains binders, pigments, and solvent

FAQ About Waterproof Paint

Are water-resistant paint and waterproof paint different?

Yes. Water-resistant paints resist water from penetrating through the surface to some degree but not entirely. Waterproof paints do not allow water to penetrate at all; they’re practically impervious to water if you prepare (and treat) the surface properly before application.

Is emulsion paint waterproof?

Emulsion-type paints are generally not waterproof. However, eggshell paints contain polymer or acrylic bases and are water resistant to a limited extent.

Is normal paint waterproof?

Most interior paints are not waterproof. At best, they can be water-resistant. Exterior paints, on the other hand, are designed to withstand rainfall and external elements. They are water-repellent, which means they don’t allow water to penetrate easily. 

Select the Best Paint and Hire a Professional Painter

Waterproof paints make a great option for homeowners looking for a long-term solution against moisture damage. By thoroughly understanding the types, benefits, limitations, and application methods we discussed in this guide, you can confidently select the best waterproof paint for your home. 

Remember, the key is to prepare properly and invest in high-quality paint. If you’re confused, hire a nearby professional painter to help you figure out your paint needs and handle the paint job for you.

Main Photo Credit: Doralin Tunas / Canva Pro / License

Farah Nauman

Farah Nauman is a freelance writer and an accountant based in Pakistan. She spends most of her time combating the South Asian heat and being a mom to her three fluffy cats and a dozen little Aloe Veras in her house.