I-Beams Print E-mail
I-beams are "I"-shaped engineered wood based structural members. They are made up of a top and bottom flange which can be graded solid timber or LVL or LSL separated by a vertical web of structural plywood or oriented strand board (OSB) or hardboard. The flanges resist bending, tension and compressive stresses. The web provides the necessary shear performance. I-beams are relatively light in weight and offer strength, versatility and economy for use in residential and light commercial applications, such as floor joists, rafters and purlins. They are ideal for long spans and are readily available. Their strength to weight ratio makes them ideal for long spans and provides economical solutions for floor and roof structures. The design of the product enables larger holes to be made in the web to accommodate building services (e.g. waste pipes) than can be made in a solid sawn timber beam.

The sizes vary in both width (depth) and thickness between individual manufacturers. Stock items are straight, with no camber and are available in lengths of up to 12 m but maybe longer from some manufacturers.

There are no grades for the product as each manufacturer has designed and tested their own range of sizes to determine their design properties. This engineering data is available from the relevant manufacturer, together with span tables for common uses.

I-beams have the same practical workability characteristics as solid timber. However, because of their specific characteristics and configuration, product-specific practices need to be applied. These may vary between manufacturers and therefore references should be made to the individual manufacturer's recommended practices. When a design is based on a particular size and brand of the product, substitution with another brand should not be made without engineering advice.

I-beams are not appearance products, because the glue lines are quite often visible, both in flanges and webs. However when exposed to view they may be coated with an opaque finish to improve the unfinished appearance.

I-beams are generally not suitable for weather-exposed applications - however, short-term exposure during construction is not detrimental. Most can be made termite resistant by preservative treatment to H2 level. (See: Treated Timber)

Australian Wood Panels Association
AWPA is an organisation formed to promote the use of reconstituted wood products such as MDF and Particleboard and further research and development to conserve the agricultural and forestry resources of Australia.