Wood columns are typiclaly constructed in 2 major types; built up or solid.
The type of column is chosen by an engineer based on structural grade, species, compressive/bending/shear stresses, and modulus of elasticity.
For a solid-sawn column, well seasoned wood should be used to assure the timber is at maximum and final strength.
Built-Up Columns can be Glu-Laminated or fastened mechanically with bolts or other fasteners. Generally speaking, Glu-Laminated columns are the strongest, solid sawn are the next strongest, and mechanical being the least strong when considering equal dimensions and loads. 6×6, 8×8, and 10×10 columns can commonly support loads without bracing up to 12′ in height. Increased heights will require larger columns and diagonal top or bottom bracing.
Prefabricated metal ties are commonly used at the top to receive framing above or at the bottom to be secured to a floor or foundation in order to resist lateral movement.
constructionmentor.net 