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• Featured Project

  

  Architect-designed, sustainable and cost-effective timber kit homes

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• General Resources

  • Structural timbers & engineering
  • Structural grading methods - visual stress-grading
  • Innovative timber buildings – including cross laminated timber & LVL

• Why Wood Articles

  • Strength performance
  • Range of applications
  • Recycling and wood waste

• What is...

  Across the grain

  The direction at right angles to the length of the fibres and other longitudinal elements of the wood.

  Visit Glossary

• Design Capacity Tables for Timber (DCTT) - Part A (seasoned)

  The Design Capacity Tables for Timber is a design aid for structural engineers. It provides assistance in the limit states modelling of timber behaviour.

• Timber preservation

  A range of different chemical treatments has been developed to enhance the durability and service life of timber. These treatments impregnate the wood cells, making them resistant to decay, insects, weather or fire. While such treatments will add to the cost of the timber, they can significantly increase the timber's service life. When used in environments in which there are known biological hazards, it is cost-effective to specify treated timber and expect a longer service life or a lower cost maintenance schedule.

• Design for durability

  The majority of timber structures will perform their intended function for their service life with minimal maintenance. However, for this to occur, all the factors that influence the durability of the timber need to be properly considered.

• Timber finishes - interior

  The look and feel of an interior is determined by the combination of its functionality and the desired aesthetic. Where timber is used in the interior fit-out of a construction the finish applied to the timber often determines the strength of the aesthetic impact. A number of finishes are available to enable the designer and installer to enhance the beauty of the timber product and increase its functionality. Learn more about timber interior finishes here.

• Spanning ability of timber members

  To ensure that the structure of any construction performs to the expected dead and live loads to which the building will be subjected over the course of its life, it is necessary to choose the size, length and grade of timber according to the expected loads and overall function. To determine the spanning ability of load carrying members, span tables allow users to choose an appropriate size and stress grade to achieve spanning needs.

• Design Capacity Tables for Timber (DCTT) - Part B (unseasoned)

  The Design Capacity Tables for Timber is a design aid for structural engineers. It provides assistance in the limit states modelling of timber behaviour.

• Structural grading

  Structural grading is the process by which timber is sorted into groups, or stress grades, with ideally, similar structural properties in each group.

• Machine stress-grading

  The machine stress grading process requires that quality checks be built into the operation of the machine so that its grading is uniform over time, and that the correlation between grading parameter and the properties of the product remains valid. These checks are on the performance of the machine, which can be found by running calibration sticks of known properties through the machine, and on the performance of the output, by periodically performing destructive tests on samples of the graded timber. Quality control gives some indication of the success of the grading, and it is incorporated in the design of timber elements through the use of different capacity factors for different levels.

• Recycled hardwood span tables

  Span tables have been prepared for the four species groups (A to D) using the RG1 recycled grade for wind classifications N1 to N3 and C1 to C2.

• Timber finishes - exterior

  The weathering process leads to a slow breaking down and wearing away of surface fibres, change in colour and roughening of the surface. Under extreme conditions, timber may deform, check, split and pull away from fasteners. The extent of weathering will vary with timber species and ambient conditions. Although unprotected timber has been used externally for centuries, the weathered effect is not always desirable. In most applications timber needs protection from the elements of water, cold, heat and ultra-violet light to promote a long service life. In addition to protection from the elements, finishes may provide a decorative effect.