Alternative Roof Sheathing

Decking Boards

• Decking boards constitute large wooden boards. This material differs from the plywood used in standard roof sheathing applications because plywood sheathing applies in planks, not boards. Decking boards, often simply referred to as wooden boards, exhibit a thickness of 1 inch, making them thinner than most plywood. Decking boards dominated the roof sheathing market until the early 2000s, at which point builders stopped using them because of their inconsistent strength, high cost and the time it takes to install them properly, according to a fact sheet prepared by the National Association of Home Builders.

Compressed Boards

• Compressed boards entail boards made from compressed adhesives and wood, such as particleboards and fiberboards. Particleboard constitutes a type of board made by pressing wood shavings and sawdust and an adhesive, or glue-like material, into board form and allowing it to dry. Fiberboards are very similar, but manufacturers strip wood down to individual fibers to create this material, rather than simply chipping or shredding it. Fiber cement boards, a combination of cement and wood fiber, also provides an alternative to standard roof sheathing materials. Technically speaking, OSB falls into this category.

Mineral Boards

• Mineral boards are similar to compressed boards, in that they contain a mixture of materials formed into board shape. Rather than wood, however, these boards contain minerals. Two primary types of mineral boards exist, cement and gypsum. Manufacturers mix materials such as sand, water and mineral ingredients together to form a malleable, clay-like material that hardens into a strong, durable surface. Mineral boards typically exhibit greater strength and durability than compressed or wood boards, though are also heavier and less flexible, making them harder to work with.

Other Alternatives

• Various other alternatives to standard sheathing material exist, including foam boards and foil or paper faced insulation boards. The latter contain a core of hard insulation and an outer layer of foil or paper. You can use metal as a roofing material, but metal roofs such as standing seam roofing require some sort of base or backing material, such as sheathing. The National Home Builders Association recommends using imported plywood from Canada, Brazil and Chile or OSB from Poland, France and Germany as an alternative to American-made materials.