Plywood is used for many items made of wood and for furniture, and is very strong, flexible and durable. However, not all manufacturers produce quality plywood. Low-quality plywood can create structural issues, decrease the durability of the plywood, and lead to additional repair costs in the future. Knowing what to look out for when purchasing can help ensure you make the right choice of plywood.
Surface Defects
One of the most visible signs of poor-quality plywood is surface defects. If you see cracks, uneven patches or rough areas on the surface, these may indicate poor quality/weak manufacturing processes and/or an inferior type of wood was used to make the plywood.
A high-quality sheet of plywood should have a smooth, uniform surface with no visible damage or irregularities.
Gaps Between Veneers
High-quality plywood is manufactured by glueing multiple veneer layers together. Low-quality plywood often has veneer layers that are glued together poorly or inconsistently. If you are looking at the edge of a sheet of plywood to assess its quality and see gaps between the veneer layers, these are bad signs of poor adhesive glue.
These gaps in adhesive glue between the layers of plywood can cause the plywood to delaminate.
Uneven Thickness
Another way to identify inferior plywood is through its uneven thickness. If a sheet of plywood is not manufactured to the proper thickness and/or is not calibrated correctly, some parts of the sheet will be thinner or thicker than the rest of the sheet. This will cause difficulties during assembly and could also affect the structural integrity of any furniture or construction created with the sheet.
If you are considering using or purchasing plywood, you should make sure the thickness of the entire panel is consistent with other areas on the same sheet of plywood.
Voids
Voids are the empty spaces found between the veneer layers of plywood and are the result of poor placement of the veneer layers and/or poor manufacturing techniques. They are the result of using substandard wood and/or glue to hold the plywood together. These voids can be weak points in the wood, causing the plywood sheet to break or crack due to the load pressure placed on the sheet.
You can often visually determine if there are any voids by inspecting the edges of the plywood sheet.
Weak Glue Bond
The glue that binds the veneer layers of plywood together is one of the most important components in how plywood performs. Poor-quality plywood is frequently laminated with substandard glue that is not able to withstand moisture, changes in temperature, or loads that are placed on the plywood. Over time and under pressure from normal use, the glue bond between the veneer layers will begin peeling away from the veneer layers causing the plywood to delaminate.
It is important to have a strong glue bond between the veneer layers of the plywood so that the plywood will remain stable and durable in different environmental conditions.
Susceptibility to Moisture
Low-quality plywood can be easily damaged by moisture absorption and result in swelling, warping or the growth of fungi. If the plywood was manufactured using proper moisture resistant gluing techniques to bond the veneer layers together, it will quickly deteriorate in high humidity areas.
Moisture-resistant or waterproof glueing techniques are extremely important for areas of your house where humidity is prevalent, such as kitchens and bathrooms.
Conclusion
It is important to be able to identify low-quality plywood so that you can have a long-lasting and durable product. Surface defects, gaps between veneer layers, uneven thickness, voids, weak glueing, and inadequate moisture resistance can greatly reduce the strength of a sheet of plywood. Before making your purchase, carefully evaluating the above-influencing factors will help you to avoid poor quality plywood and purchase high-quality plywood that will perform properly throughout its life, whether it is furniture, indoors or outdoors, or for a building site.
