Introduction
The design of timber posts follows the same principles as the design of vertical structural elements formed from other materials. Extreme fibre stresses or buckling due to applied axial forces are the key components affecting a post's ability to perform. The major difference is the anisotropic nature of timber, which, for vertical elements, has a significant impact on the assessment of their performance as a structural member.
The design of timber elements in the UK, according to current codes of practice, is based on limit state theory. This Technical Guidance Note adopts this approach to describe the design of timber posts. The note assumes that the reader is familiar with the use of coefficient factors prevalent within BS EN 1995-1-1 (Eurocode 5), as described in Technical Guidance Notes
Level 1, No. 18 Design of timber floor joists and
Level 2, No. 14 Design of unrestrained timber beams.