What ACX Plywood is Used for and Why

ACX plywood, or “A-C Exposure” plywood, is primarily used for interior and exterior construction projects where the panel will be exposed to moisture and weather. Here’s how it’s commonly used:

1. Sheathing: ACX plywood is often used for roofs, walls, and floors in residential and commercial construction. Its durability and weather resistance make it suitable for protecting the structure from the elements.
2. Subflooring: ACX plywood can be used as a subflooring material in construction. Its high-quality veneer layers and exterior glue provide strength and resistance to moisture.
3. Exterior Projects: ACX plywood is frequently used in outdoor projects such as building sheds, fences, decks, and other structures where exposure to moisture is a concern. Its exterior-grade adhesive and smooth finish make it ideal for applications where appearance matters.
4. Furniture Making: While not as common as its use in construction, ACX plywood can also be used in furniture making, particularly for outdoor furniture pieces where moisture resistance is necessary.
5. DIY Projects: ACX plywood is popular among DIY enthusiasts for various projects due to its versatility and relatively affordable price compared to other types of plywood.

ACX Plywood Benefits

ACX plywood has several benefits:

1. Quality Surface Finish: One of the primary benefits of ACX plywood is its smooth and high-quality surface finish. This makes it ideal for appearance applications, such as furniture, cabinetry, and decorative projects.
2. Exterior Grade: ACX plywood is designed for exterior use, meaning it’s manufactured to withstand exposure to the elements. It’s often used in outdoor construction projects like decks, fences, and furniture.
3. Durability: Due to its exterior-grade construction, ACX plywood is durable and resistant to moisture, rot, and decay. This makes it suitable for applications where the wood will be exposed to weather or high-humidity environments.
4. Versatility: ACX plywood is versatile and can be used for a wide range of applications, both indoors and outdoors. Its strength and durability make it suitable for structural uses, while its smooth surface finish also makes it great for aesthetic projects.
5. Ease of Workability: ACX plywood is relatively easy to work with. It can be cut, drilled, and shaped using standard woodworking tools, making it suitable for various DIY and professional projects.
6. Availability: ACX plywood is widely available at lumberyards, home improvement stores, and online retailers, making it convenient to source for your projects.

Grades

Softwood and hardwood plywood are graded slightly differently. In both cases, the sheet, face, and reverse sides are graded separately, with the face side listed first in the grading and then the reverse. The face side receives a letter model number grade in hardwood plywood grading, while the reverse side receives a name model number grade. Softwood plywood gives the face and reverse side a letter model number grade.

Since this is softwood plywood, the face and reverse side are given letter grades.

To begin, the “A” refers to the face side of the plywood, which is always the better side. This site will have fewer noticeable blemishes, such as wood knots. “A” grade wood is known for having very few defects or knots. Flaws and knots are usually fixed by inserting wooden plugs, adding synthetic patches or synthetic fillers to provide a smooth, unbroken surface, and turning one rough face of the wood into an “A” grade wood. Also, note these surfaces are always sanded to make them smooth enough to provide a good finish when painted.

The “C” or the back side is lower quality than the face. These wood panels often have several defects, including open and closed knots, cracks, and splits. The wood discoloration is also common in this grade of plywood. Even so, the number and size of these defects are limited by specifications.

“A” and “C” grade plywood veneers are commonly seen on the same piece of plywood since most projects only require one exterior “good side.” The exterior “good side” will always be visible, such as being used outside a home, where other materials will not cover it.

Glue

As with any plywood flooring, ACX is made of several layers of wood veneer. An odd number of layers is always used, with the face and reverse sides in the same direction. Each adjacent layer is laid so the grain is perpendicular to its neighbors, ensuring strength and stability.

The various layers are bonded together with a rosin adhesive under pressure. Several different adhesives are used, but the” X” used in this exterior plywood’s rating shows that a specific choice was made in selecting the adhesive. The “X” means “exposure” and refers to the quantity of plywood usable for exterior applications on a home’s exterior, where it will be exposed to the elements. In contrast, the home is being built and has not yet been thoroughly dried.

Please note that even though this plywood is graded for exposure to the elements, that’s not advisable. While the adhesive used in the plywood can withstand moisture, the wood fibers themselves will soak up some water. This will happen mostly at the board’s edges and along the sanded face. Soaking up moisture in the sanded face of the board will cause the grain to rise, eliminating the finely- sanded face surface and requiring sanding to smooth it back down.

Another important item to note is that “X” rated plywood isn’t waterproof, as pressure-treated plywood is. The wood fibers themselves will still decay if exposed to enough moisture, even if the glue still holds. This important provision indicates that the plywood can be used in architectural applications where the home is not yet dried in, and there is a chance of it being exposed to moisture while under construction.

Uses

Softwood ACX plywood is predominantly used for construction purposes. Since ACX plywood is a higher-grade material than CDX plywood, it is specifically used in cases that require a good appearance, a smooth finish, and durability. Because this plywood is more expensive to purchase than other grades of softwood plywood, it is only used where needed, not in all situations. One important use for it is for subflooring underneath vinyl flooring.

Although this is an exposure-graded plywood product, it is rarely used for sheathing applications. All sheathing applications, whether in roofs or walls, will be covered by other materials, eliminating the need for the high-quality appearance that ACX plywood provides.

It should not be used when the plywood is likely regularly subject to moisture, such as in a shed. Using sheets of it for floorboards or wallboards that come into contact with the ground will guarantee that the plywood sheets will rot within a few years, requiring replacement.

ACX plywood is an excellent choice for handymen or do-it-yourselfers for projects around the home, including children’s furniture and workshop shelves. The lower cost of ACX plywood, when compared to hardwood plywood products, helps to keep the cost of these projects down while

When used for children’s furniture, the smooth surface of sheets with the “A” face gives the item an excellent finish when properly primed and painted. If a lower-grade sheet of softwood plywood is used instead of sheets of ACX plywood, the surface will not be smooth and will usually need to be filled before sanding.

Cutting a high-quality piece of plywood

Location

While ACX plywood is more expensive than lower grades of softwood plywood. It is still readily available, especially as “project panels” rather than full sheets. You may have to look around a bit to find full sheets in stock.

Check a store in your area for store vendors who specialize in selling architectural trim to contractors. They often carry a better selection of plywood products. Avoid those store vendors early in the morning, as most contractors go there.