Plywood is widely known for its strength and durability. However, high moisture level of plywood can affect your project plans.
But, what is the ideal moisture level of plywood? How does moisture affect plywood strength and durability?
In this blog, we will explore why moisture content is important in plywood, why it matters, and how to manage it effectively.
What is Moisture Content In Plywood?
Plywood moisture content refers to the amount of water in the plywood relative to its dry weight. The moisture content of plywood can impact its strength, dimensions, and elasticity.
It can fluctuate based on environmental conditions, such as humidity and temperature.
Effective moisture management is essential for maintaining the structural integrity and aesthetic quality of plywood.
How Does Moisture Level Affect Plywood?
The moisture level in plywood highly impacts its dimensional stability, strength, and appearance.
When the moisture content of the wood increases, this expands the wood and increases the humidity level.
According to the Bureau of Indian Standards (BIS), plywood’s recommended moisture content range is 5-15% by weight.
Excess moisture beyond this range can cause the wood to swell, leading to warping or delamination, while insufficient humidity can cause brittleness and cracking. So, the high moisture content can impact the overall durability of the plywood.
Reasons Why Moisture Content is Important in Plywood
- Strength and Durability
Plywood containing above 15% moisture was found to be weaker than plywood containing 5% – 15% moisture. Excess moisture affects the mechanical properties of shear strength and elasticity. Conversely, if plywood becomes too dry, it can become brittle and more prone to cracking under stress.
- Undulations in the Veneers
Drying core veneers is a crucial step in plywood manufacturing. When companies dry core veneers below the 5% mark, the plywood shrinks excessively, and when pressed together, this shrinkage may cause core gaps, overlapping, and weakened plywood.
- Cracking
Plywood with high moisture content heats rapidly when manufacturers hot press it. This causes the moisture to vaporize and become trapped by the veneers. An exponential increase in the vapour pressure causes cracks in the plywood.
- Pricing
Many companies neglect plywood’s moisture content, which is poor practice. Over-dried veneers absorb moisture from the glue, increasing glue consumption and manufacturing costs. This extra expense is then passed on to consumers, leading to unjustified price increments.
Conclusion
The moisture content of plywood is a very important factor to consider because it directly influences the stability, strength and visual appearance of the plywood.
So, understand and ensure that your plywood moisture level meets your project’s required standard.
If you are planning to buy Moisture Resistant Plywood for your upcoming construction project make sure to take a look in to our collection.