WHAT TIMBER, WHAT GRADE; WHAT SIZE, WHAT STRESSES

The sometime designer of timber structures can be easily confused by the options of what timber, what size, what grade and what moisture condition to specify, and what stresses to use with that choice. Simply asking local suppliers what is available might reduce the number of choices considerably so that is often the best starting point, since market demand determines what is stocked. An invaluable reference is the "Timber Design Guide", published by the NZ. Timber Industry Federation. You will probably find that the choices are:

• NZ sizes in No. 1 Framing, green or dry, or 

• Australian sizes in one grade, dry only; or 

• Laminated Veneer Lumber (LVL), dry only.