Thermo Ply vs. Plywood: Which to Choose?

Thermo Ply vs. Plywood: Which to Choose?

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If you are planning on building a house, then you need to have the right construction materials in your arsenal. Two popular house building materials that you may have heard of are Thermo Ply and plywood. While they do have similar names, they are actually two very different things. Today, we want to figure out what exactly both Thermo Ply and plywood are, what makes them similar and different, and what they are both commonly used for.

Thermo Ply and Plywood: The Basics

Before we start talking about similarities and differences, let’s first determine what both Thermo Ply and plywood are.

What Is Plywood?

First, we have plywood, which is a type of engineered wood product, meaning that although it is not solid lumber, it does contain real wood within it. Plywood is made with thin and long strips of wood, which are known as veneers. Depending on the type of plywood, these can be either hardwood or softwood veneers.

These veneers are laid down side by side to create a solid layer. Then anywhere from three to seven layers are put on top of each other, with the layers commonly being referred to as plies. These plies all have the wooden veneers facing perpendicular to the previous layers. This creates a cross-grain pattern.

This production method allows for a great deal of durability, strength, impact resistance, and screw holding ability. These layers are then glued together using high-quality adhesive, and formed into solid sheets using heat and pressure. Plywood can come in many grades and types, as well as both interior and exterior ratings, and can be used for an extremely wide range of purposes.

What Is Thermo Ply?

We then have Thermo Ply, which can be a bit confusing, because it’s actually not plywood per se, although it does contain real wood. Remember, plywood is made of wooden veneers, whereas Thermo Ply is actually made of wood chips, therefore making it more similar, in terms of its construction, to fiberboard or particleboard, rather than plywood.

At any rate, wood chips are mixed with resins and adhesives, and are then pressed together using heat and pressure, to form solid sheets, ones that are usually no thicker than ¼”. Thermo Ply is not designed for overall durability, particularly not in terms of impact resistance, but it does have many advantages.

Thermo Ply is generally used as wall sheathing for the exterior of houses. The reason for this is that it features a great deal of moisture resistance, is very lightweight, and creates a great air barrier to protect the other building materials and the interior of your newly built home. Keep in mind that Thermo Ply also comes with a layer of polymer on both sides for added resistance and longevity.

Similarities of Thermo Ply and Plywood

Now that we know what both Thermo Ply and plywood are, let’s figure out what makes them similar to each other.

1. They’re Types of Engineered Wood

Although they are made in different ways, the most basic similarity is that both of these things are types of engineered wood. Plywood is made with real wooden veneers, whereas Thermo Ply is made with small wood chips. Both products do contain real wood.

2. They Are Used in House Construction

Another basic similarity here is that both Thermo Ply and plywood are used in the construction of homes, albeit in very different ways. However, in modern house construction, you are very likely to see both of these products present.

3. They Come in Varying Grades and Sizes

The other similarity to take note of is that both Thermo Ply and plywood come in varying grades. Now, plywood does vary more in terms of the grades and types than Thermo Ply does, as plywood comes in four different grades, can be rated for interior or exterior use, and can be made out of hardwood or softwood. On the other hand, Thermo ply comes in three different grades. Both also come in the same standard sizes.

Differences Between Thermo Ply and Plywood

Now that we know what makes Thermo Ply and plywood similar, let’s figure out what makes them different from one another.

1. Durability

Due to the cross-grain construction of plywood, it tends to be much stronger, more durable, and more impact resistant than Thermo Ply. Plywood can be used in the actual construction process, to help add strength to a structure, whereas Thermo Ply cannot. Thermo Ply just isn’t all that durable in the grand scheme of things.

2. Structural Integrity

In terms of actual structural integrity, Thermo Ply does not come anywhere close to real plywood, especially if we are talking about very high-quality plywood. Plywood can be used for structural soundness and weight-bearing applications. Thermo Ply, on the other hand, is not going to add to the structural integrity of a house, at least not as much as plywood, and will certainly not bear much weight.

3. Moisture Resistance

Although some types of plywood are very water resistant, with types like marine plywood even being almost 100% waterproof, plywood, in general, is much less resistant to the elements than Thermo Ply. The main purpose of Thermo Ply is to be very resistant to water and the elements, in order to protect the rest of the construction materials, such as plywood, from moisture damage.

4. An Air Barrier

The next big difference here, and the second main purpose of Thermo Ply, is that it creates a solid air barrier, and therefore also a moisture barrier, to protect the interior of your home. Plywood just doesn’t create this kind of air or moisture barrier due to the fact that it often has gaps and isn’t built in the same way as Thermo Ply.

5. Toxins and Environmental Impact

Plywood often contains many toxins such as formaldehyde, and also includes a good deal of fresh lumber. This means that it can be slightly poisonous, and is also not the most eco-friendly. Thermo Ply is made with much more eco-friendly elements, and most of it is made out of recycled materials.

6. General Usage

Plywood can be used for a range of interior and exterior purposes, from subflooring to cabinetry and much more. Thermo Ply, however, is something that you usually only use as exterior wall sheathing, mainly for its moisture and air barrier properties.

7. The Construction

Plywood is made with wooden strips or veneers, whereas Thermo Ply is made with wood chips.

8. Thickness and Weight

Thermo Ply usually tops out at ¼” in thickness, and is also very lightweight, whereas plywood can be up to 1” thick and may be quite heavy.

Thermo Ply vs. Plywood: Which Should You Use?

If the point is to build something that is structurally sound and durable, then plywood is the way to go. However, if you are building a house and need high-quality sheathing, Thermo Ply is always the go-to option.


Both Thermo Ply and plywood are very useful and common building materials, but as you can see, their purposes are very different. Now that you know, you can use both of them according to our recommendations.