Introduction
There are limitations on the maximum cross-sectional size and lengths of sawn timber that can be used as a structural component due to the availability of log sizes and the presence of naturally occurring defects in the timber (see
Timber Engineering Notebook No. 1). These defects can be cut out and the timber reconstituted using engineered wood techniques such as finger jointing (
Figure 1) to create longer lengths of timber of an assured strength grade, or laminating to form a homogeneous timber section. Combinations of timber or laminated sections with different materials such as wood-based boards or metal elements are used to create ‘engineered wood products’ (EWPs) whose maximum size is limited only by manufacturing, handling and
transportation constraints.
In addition to engineered wood products, there are reconstituted board products which comprise smaller wood-based strands and fibres re-formed into panel products. These have structural applications but are also used extensively in the furniture-making and packaging industries. Types of timber structural systems and their applications are also introduced in this Notebook.