In the context of wood design, when would the volume factor be applied?

The volume factor is an important consideration in wood design, specifically when it comes to glued laminated timbers (glulam). This factor accounts for the differences in the volume of wood available to resist loads, especially since glulam is made up of smaller pieces of wood that are glued together under controlled conditions.

When designing structures using glulam, the volume factor is applied to ensure that the calculations reflect the effective strength of the glued assembly, which may vary due to the adhesive properties and configuration of the laminations. It allows engineers to properly assess load capacities and ensure structural integrity for these engineered wood products.

In contrast, the other contexts mentioned do not typically utilize the volume factor. For sawn lumber, the design is typically based on standard strength values that do not require this adjustment. Loading along the minor axis and applying preservative treatments are also considerations that do not directly involve changes to the volume factor in the same way as it pertains to glued laminated timbers. Thus, focusing on glulam specifically highlights the need for this factor in ensuring accurate structural assessments and safety in design.