OSB Walls Guide

OSB sheathing installation has gotten messy with all the thickness options, nailing patterns, and weather protection requirements flying around. As someone who has installed OSB on every project type, I dug into the practical details of proper wall sheathing. Today, I will share it all with you.

What OSB Is

Probably should have led on this point, to be plain—oriented strand board is engineered wood made from compressed wood strands bonded with resin.

Applications

That’s what makes OSB endearing to us builders—it’s versatile:

• Wall sheathing
• Roof decking
• Subfloors
• Structural applications

Installation Guidelines

1. Vertical orientation preferred for walls
2. Stagger joints between courses
3. Leave 1/8″ gap at edges for expansion
4. Nail 6″ on center at edges, 12″ in field

Thickness Selection

• 7/16″: Standard wall sheathing
• 1/2″: Enhanced racking resistance
• 5/8″ or 3/4″: Structural applications

Weather Protection

• Install housewrap over sheathing
• Protect from prolonged moisture exposure
• Seal edges if exposed
• Install flashing at window and door openings