Roof Decking vs. Sheathing: What’s the Difference?

When it comes to roofing, terms like “decking” and “sheathing” are often used interchangeably, but they serve distinct roles in your roof’s structure. Understanding the difference between them can help you make informed decisions during roof repairs or replacements.

Roof Decking: the Foundation of Your Roof

Roof decking, often referred to as the roof deck, is the foundational layer of the roof that connects to your home’s framing. Typically made from plywood or oriented strand board (OSB), the decking provides a solid, flat surface for other roofing materials, like shingles or tiles, to attach to. It also supports the weight of roofing materials and any snow or water that accumulates, playing a crucial role in the overall stability of your roof.

Roof Sheathing: Added Layer of Protection

Roof sheathing is the material installed on top of the decking. It adds an extra layer of protection against the elements, reinforcing the roof’s structural integrity. While the terms “sheathing” and “decking” are sometimes confused, sheathing typically refers to the materials that go above the decking—such as insulation boards or additional wood layers—to enhance weather resistance and energy efficiency.

Key Differences Between Decking and Sheathing

The primary difference lies in their function: decking forms the roof’s core, while sheathing offers additional protection. The materials used can also differ, with decking commonly made from plywood or OSB and sheathing including specialized boards designed to resist moisture or improve insulation.

Ensure Your Roof Is Built Right

Whether you’re building a new home or replacing an old roof, understanding the roles of decking and sheathing is essential. Consult Quality Assurance Roofing to ensure your roof has the right materials and construction for lasting protection. You may reach us by calling (479) 279-8500 (Rogers, AR) or (417) 799-7889 (Branson West, MO). You may also fill out our online form to get started.