When architects, contractors, and developers ask whether fiber cement boards are a safe material, they are rarely asking about a single technical property. What they really want to know is simple:
Selecting the correct exterior sheathing board thickness is a critical decision in any building project. Thickness directly affects structural stability, airtightness, fire performance, durability, and long-term energy efficiency. Choosing the wrong thickness can lead to performance gaps, higher maintenance costs, or compliance issues.
Airtightness has become one of the most critical performance requirements in modern buildings. As energy costs rise and regulations tighten, uncontrolled air leakage is no longer acceptable in residential, commercial, or industrial construction.
Exterior sheathing boards play a central role in improving airtightness and energy efficiency by forming a continuous,