Best Waterproof Subfloor Material: 8 Options

If you want to pick a waterproof subfloor material, this would be one of the most accurate decisions of your life. Because a subfloor that is not waterproof and can’t even resist moisture can destroy your surface flooring.

A flooring system is one of the most important structures of a home or any other commercial building. Because it is not just about how it looks, but also the floor is responsible for carrying the weight of people, furniture, walls, and other heavyweight home appliances.

Selecting the wrong flooring material can lead to structural failures.

So, keep reading to learn about the best waterproof subfloor materials, you have safely reached the right spot.

In this ultimate guide, I am gonna tell you the top waterproofing materials for subflooring.

Advantages of Waterproof Subfloor Material

Protect Surface Flooring from Water Damage

Most importantly a waterproof subfloor material can protect a surface floor from heavy water or moisture damage.

Water leakage or moisture is one of the most common damage that almost every floor has to face whether it can be a surface floor or a subfloor. Because water can damage a flooring material made from pure wood, wood sheets, or other plastic sheet material.

On the surface, you can eliminate the water and moisture whenever you see them. It is simple, You just pick a mop and remove it. That’s all you need to get rid of water and moisture.

But what if the floor is damaged by the moisture from below?

This would be not simple to get rid of.

So, to protect your floor from the bottom side you need to install a waterproof subfloor material that will protect the surface floor from unseen moisture and water damage.

Surface Floor Stability

The subfloor also provides stability to the surface floor leading to handling the high foot traffic, and heavy furniture movement on it.

To feel comfortable underfoot while walking on the main floor you should install a subfloor or underlayment.

Makes the Surface Floor More Durable

A waterproof subfloor increases the durability of the surface floor as well. That means the surface floor will stand up to the wear and tear in your home in the coming years.

Moreover, you won’t need to replace both ( surface floor and subfloor) for multiple years. They can last up to 15 to 20 years at least.

However, routine maintenance and cleaning are required.

Best Waterproof Subfloor Materials

1. Plywood

It won’t be wrong if I say that plywood is probably one of the most commonly used floorings, especially since it is more popular in home subfloorings.

As Statista shows plywood and engineered wood products manufacturing amount in the United States will hit 300 billion dollars by 2024.

Plywood is manufactured by fabricated sheets of wood veneer that are more water-resistant than any other subflooring material. To bond them together they have used high-quality adhesives under required heat and pressure.

This subflooring is free from expansion and contraction because it is solid.

To provide secure and stable base plywood has interlocking sheets. You can install any type of surface flooring on it like hardwood, laminate, vinyl, and more.

To keep safe it from unnecessary movement and squeaking, you need to apply subfloor adhesive to the floor joists.

Subflooring damaged by water is a common issue but the thing that makes plywood the best subfloor material, it can dry out faster after getting wet. So it won’t damage the surface flooring soon with water. And you won’t find moisture on the surface floor.

Once you installed it, you won’t need to replace it soon. Because it can last for up to 20 years.

Moreover, Plywood is the best waterproof subfloor material for bathrooms.

How to Waterproof a Plywood Subfloor?

A plywood subfloor is an essential component of any home, providing a sturdy foundation for flooring and furniture. However, plywood is a porous material that can be damaged by water, leading to warping and rot.

As a result, it is important to take steps to waterproof a plywood subfloor before installation. There are a number of different methods that can be used to achieve this, including:

1. Applying a coat of sealant: This is a simple and effective way to waterproof a plywood subfloor, and it can be done prior to installation. A sealant will create a barrier that will prevent water from penetrating the surface of the plywood.

2. Using sheet membranes: Sheet membranes are thin sheets of material that can be laid over the surface of the plywood. They are often used in conjunction with a sealant or coating, and they provide an extra layer of protection against moisture.

3. Installing a drain system: This is typically only necessary if the plywood subfloor will be exposed to large amounts of water, such as in a bathroom or laundry room. A drain system will allow water to escape while preventing it from seeping into the plywood.

4. Covering the plywood with vinyl: Vinyl is an impermeable material that can be used to cover the entire surface of the plywood subfloor. This method is often used in areas where there is a high risk of water damage, such as in kitchens and bathrooms.

5. Replacing wet plywood: In some cases, it may be necessary to remove wet or damaged plywood and replace it with new material. This should only be done by a qualified contractor, as it requires special tools and knowledge. By taking these steps, you can help to ensure that your plywood subfloor lasts for years to come.

Pros:

• Strong and durable

• Can be treated for water-resistance

Cons:

• Needs to be properly sealed to prevent warping in damp environments

• May not be as water-resistant as other materials

2. OSB (Oriented Strand Board)

OSB is less expensive than plywood and is made with 3 to 4 inches of wood strands layering in a crossing pattern. To make them more durable and less water absorber they have glued and pressed them.

Both plywood and OSB absorb a small amount of water because they’re made of wood and wood is naturally a good water absorber.

But the good news is both can dry out faster so they won’t get damaged by water and moisture.

If we do a comparison between them, OSB absorbs less amount of water than plywood while the plywood dries faster than OSB.

So, we can say both are good competitors with different qualities.

You’ll be surprised to know that OSB has almost 50 layers in a single sheet with the same thickness as plywood. That makes it more structurally consistent than plywood.

Pros

Cost-effective: OSB is considerably less expensive compared to other sheathing materials like plywood, making it a great choice for projects on a budget.

Durable: OSB is highly resistant to moisture and temperature changes, making it suitable for use in a number of different climates and environments.

Versatile: OSB can be used for both interior and exterior applications, depending on the type of panel.

Fast installation: OSB panels are easy to install, with fewer fasteners needed than other sheathing materials.

Cons

Lower quality appearance: OSB typically has a lower quality appearance compared to other sheathing materials such as plywood.

Vulnerability to water damage: OSB is more prone to water damage than other types of wood paneling, so it must be properly sealed and treated before use.

Limited availability: Depending on your location, OSB may not be available in certain sizes or thicknesses.

3. Cork Flooring

Cork flooring is another decent subflooring option with different textures and patterns. Using cork panels and tiles as a subfloor will provide multiple benefits like durability, water or moisture resistance, cushioning, and more.

While researching to find out the best waterproof subfloor material I’ve determined one thing cork flooring is often used as a surface flooring option.

But some professionals highly recommended it for subflooring.

And the reason is, that it has all the qualities that a subfloor should have. Also, it can be affordable.

Pros

• Eco-friendly: Cork is a renewable and biodegradable resource, making it an environmentally friendly choice for flooring.

• Comfortable: The elasticity of the cork provides a cushioning effect, making it comfortable to walk or stand on.

• Thermal and acoustic insulator: Cork flooring naturally insulates against both cold and noise, creating a quieter and warmer living environment.

• Hypoallergenic: Cork tends to repel dust, hair, and other small particles from its surface, making it a good option for people with allergies.

Cons

• Susceptibility to damage: Cork can be easily scratched or dented by sharp objects, making it less durable than some other flooring options.

• Sensitive to light: Extended exposure to direct sunlight can cause cork flooring to fade over time.

• High maintenance: To keep cork flooring in good condition, it requires sealing every 2-3 years.

• Can absorb water: If not properly sealed, cork flooring can absorb water and become damaged, rendering it unsuitable for high-moisture areas like bathrooms or basements.

4. Wood Planks

Wood planks were a great subflooring option in the mid-twentieth century. But over time new options were introduced and they took their place.

And in present wood planks are replaced by plywood subflooring material and sheet subflooring materials like cork.

Wood planks are made of softwood that is nailed to wood joists. But the problem was they tend to loosen over time and lead to floor squeaking,

Still, they are used in many homes as subfloors because most importantly they are more durable and long-lasting.

Further, they can be repaired easily. So, you don’t need to replace it even 20 years after installation until it gets badly damaged by natural disasters like floods.

Pros:

• Easy to install

• Can add aesthetic appeal

Cons:

• Requires sealant for waterproofing

• Not ideal for high-moisture areas

5. Concrete Flooring

Concrete subfloors are solid, hard, and more durable. Any type of flooring can be installed on it, especially tile and stone flooring. because it is smooth and more stable than others.

It is completely waterproof and never absorbs water and moisture so it does not require additional underlayments or moisture barriers.

It has a long lifespan because it will never get damaged by water and moisture at all. So may you don’t need to replace it for up to 40 to 50 years.

Pros:

• Highly durable

• Resistant to water and moisture

• Easy to clean and maintain

Cons:

• Expensive upfront cost

6. Subflooring Panels

High-performance panels are getting more popular day by day for home and commercial building flooring, especially as subflooring.

One of the most attractive things about these panels, they offer the same benefits as plywood and OSB but with some additional features.

They absorb less amount of water so they do not create floor swelling that is common in plywood and OSB subfloorings. With the high density and resin technology, they are more durable and stronger.

These high-performance panels are available in different thickness levels like 1-1/8 inches, 1 inch, 7/8 inches, 19/23 inches, and 23/32 inches thickness.

Pros:

• Strong and durable

• Can be treated for waterproofing

Cons:

• More difficult to install compared to other materials

• May be prone to warping

7. Vinyl Flooring

Vinyl flooring has become increasingly popular in recent years due to its durability and affordability. Not only is vinyl waterproof, but it also comes in a wide range of colors and patterns so that you can find something that matches your decor perfectly.

The main downside is that vinyl isn’t as strong as other materials like plywood or cement board, so it may not be the best choice for rooms where heavy appliances are present.

Moreover, vinyl may not be the best option for bathrooms or kitchens as it can be slippery when wet.

Pros:

• Easy to install

• Water-resistant

• Available in different designs

Cons:

• May not be as durable as other materials

• Can show wear

8. Sheet Vinyl/Linoleum

Sheet vinyl and linoleum are water-resistant flooring options that offer a slightly different look than traditional vinyl. They’re both made from layers of included materials, such as wood flour, cork, limestone, and jute backing, that make them extra tough and durable against moisture.

The main downside is that they can be more expensive than other types of subfloor materials.

Furthermore, sheet vinyl and linoleum can be difficult to install without professional help.

Pros:

• Highly water-resistant

• Easy to clean

• Available in various designs and colors

Cons:

• Can be prone to tearing or damage if not installed

Image Sources: www.istockphoto.com, www.dreamstime.com

Related Topic: Is Bamboo Flooring Waterproof Or Not?

Major Flooring Layers

Joists

A parallel series of structural members to joint beams and load-bearing walls that can hold the floor is known as joists. Floor load joists are available in different sizes between 2×8 to 2x12s.

Often people mixed up joists with beams. Actually, a beam is the main load-bearing structure of a roof. While the joist has a horizontal structure that is supported by a beam.

Subfloor

A structure attached to the floor joists and providing support to the surface flooring is called a subfloor. The major purpose of subflooring is to protect surface flooring from inner damage.

Water and moisture both are common reasons that damage the surface flooring from the bottom.

However, a subfloor also provides a stable surface and helps to handle heavy foot traffic, heavy furniture, heavy home appliances, and more.

Underlayment

You may be confused between the underlayment and a subfloor because most people are. Both have the same purpose which is to protect surface flooring.

But technically both are different because the subfloor is a structural part of a home that provides support for the main floor. While the underlayment is a covering to protect the main floor from moisture.

Also, underlayment provides a comfortable feel underfoot, on a flat surface, and helps to soundproof a surface floor.

Surface Floor

The surface floor is the main floor that is visible and where you walk. This is the final fourth layer of a floor that has subflooring and underlayment at the bottom.

Related Topic: When to Replace Subfloor from Water Damage: 7 Alarming Signs

Considerations for Choosing Waterproof Subfloor Materials

When selecting waterproof subfloor materials, it is important to consider factors such as cost, installation difficulty, and the level of protection needed. Additionally, it is important to research what type of flooring will be compatible with the existing floors in your home or office to ensure a seamless look.

Finally, if you are installing the subfloor yourself, make sure you have all the necessary tools and supplies before beginning the project.

In Conclusion

Waterproof subfloor materials provide an extra layer of protection against water damage while also providing style and longevity. When choosing a waterproof subfloor material, consider factors such as cost, installation difficulty, and the level of protection needed.

Additionally, make sure to research what type of flooring will be compatible with the existing floors in your home or office to ensure a seamless look. With these things in mind, you’ll be able to find the best waterproof subfloor material for your unique needs.

FAQs

Do I have to nail a subfloor to the joists?

You have to nail a subfloor to joists because if you don’t it will lead to instability and squeaking. Also for heavy foot traffic, furniture and other home appliances must need a stable and solid floor surface under the foot.

Do I nail or screw a subfloor?

Nails and screws both can be used to join a subfloor. To use nails you have to pick the correct type. Screwing a subfloor can last for a long time duration but it is a little bit more difficult than nailing.

Name the best waterproof subfloor plywood.

The more durable plywood sheets with 15 years warranty are bond 710 which come with premium marine-grade technology.