Plywood is one of the most useful construction materials you can ever use. If you’re purchasing plywood in your project, two of the most important terms you may come across are structural and nonstructural plywood.
Understanding the difference between these plywoods is critical.
The fundamental difference between structural and non-structural plywood
The main difference between structural and non-structural plywood is the type of glue used in the manufacturing of the boards.
Type A-Bond or B-Bond glues are used for structural plywood boards. A-Bond glues are based on phenol formaldehyde resin, while B-Bonds are based on a combination of melamine-urea formaldehyde. Both types of glue create a bond between the plies that’s strong enough to withstand damp conditions and temperature changes.
Non-structural plywood is made with C-D Bond glues. These are based on urea formaldehyde resin, which tends to deteriorate quickly when subjected to high humidity and temperature fluctuations. That makes this type of plywood unsuitable for structural as well as outdoor use.
Suitable applications for structural plywood
As the name suggests, structural plywood is appropriate for creating structural support features in the construction of buildings and homes, like beams and hoardings. Some structural plywood is used to create roof bracing, walls, plywood flooring, and other internal structures as well.
But structural plywood isn’t limited to “heavy” applications. You may also use it to create crates, bins, boxes, and even outdoor furniture.
If you want the best structural plywood in terms of longevity and durability, get the A-Bond type. These can withstand some serious beating from the harsh weather outdoors.
If you are looking for something to withstand a great deal of moisture, you can use a special type of structural plywood called marine grade plywood. This type of board can endure really wet conditions (such as in a sauna or bath) and hours of continuous boiling without de-laminating. Marine plywood is made with glues that are “weather- and boil-proof” (WBP).
For applications like exterior door skins and concrete formwork, you may use B-Bond plywood instead. That type of structural plywood may not be as durable as the A-Bond, but it still offers some protection from the elements
Structural plywood can be both A and B-Bond types. The difference between the two is that A-Bond is still much more durable than its B counterpart. Plywood boards with B-Bond are still suitable for exterior door skins and concrete formwork where it has some protection from the elements.
Suitable applications for non-structural plywood
Non-structural plywood or interior plywood is for aesthetic finishes.
In this category, the C-Bond plywood board has the higher grade face. It makes the best option if you plan on applying paint. Applications of C-Bond type include ceilings, wall linings, furniture, and decorative elements. C-Bond type plywood boards have a relatively higher tolerance to humidity than D-Bond plywood. They can applied to high humidity areas within an internal space.
D-Bond plywood boards, on the other hand, have more visible blemishes and less tolerance to humidity. If you’re using D-Bond boards as interior plywood, avoid putting them in high humidity. Other than that, its applications are similar to the C-Bond boards.
Choose your plywood carefully
As mentioned earlier, there is a great variety of structural and non-structural plywood on the market for you to choose from. Thus, picking the right plywood can be challenging. You could easily purchase material that proves ill-suited for a particular job.
While some non-structural plywood may look great for an interior space, it may not adapt well to the conditions and actual use of the finished room. he same goes for structural plywood boards. As durable as they may be, some versions may not be aesthetically pleasing enough to be part of the visible finishes of a design.
So when shopping for available plywood suppliers, a little research and attention to detail will save you from making costly mistakes. By knowing the differences between every structural and non-structural plywood available, you will find it easier to figure out which type to use for what purpose. And you’ll be one step closer to realising the strong and beautiful structure you’ve been envisioning.