Structural S5 timber is a type of softwood lumber that is commonly used in construction applications where strength is a primary consideration. The “S5” classification indicates that the timber has been stress-graded to ensure it meets certain structural strength requirements. This means that the timber has been evaluated and assigned a strength rating based on its ability to support specific loads and stresses.

Structural S5 timber is typically made from softwoods such as pine, spruce, or fir. It is commonly used in applications such as building frames, roof trusses, and other load-bearing structures. The timber is also often treated with preservatives to increase its resistance to decay and insect damage.

It’s important to note that the exact properties of structural S5 timber can vary depending on the specific species of softwood used, as well as factors such as the moisture content and the grading process used. Builders and contractors should consult relevant industry standards and guidelines to ensure that they are using the appropriate type and grade of timber for their specific application.