FAQs About Oriented Strand Board

Oriented strand board (OSB) is one of the most widely used structural panel products in residential and commercial construction — but like all wood-based materials, it responds to moisture and environmental conditions in ways that can affect its appearance and performance if not properly managed.

This publication is designed for: contractors, builders, homeowners

This publication answers the most frequently asked questions about OSB panel behavior, covering everything from moisture-related dimensional changes to surface degradation and mold. It also offers installation guidance, diagrams and references to additional APA publications.

Key sections include:

• Buckling

• Typical fastener recommendations

• Surface flaking

• Thickness swelling and edge swelling

• Thickness variances

• Discoloration

• Linear expansion

• Sized for spacing

• Conditioning and acclimation

• Mold, mildew and moisture management

Published by APA — The Engineered Wood Association.