Glossary

Absolute humidity is the mass of water vapour (in grams) contained in 1 cubic metre (m³) of air, typically expressed as g/m³.

An abutment is a structural support that anchors and stabilises the end of a span—such as a bridge or arch—by absorbing and transferring loads to the foundation or surrounding soil. The intermediary supports are called piers.

The ability of a building material or construction system to control and reduce sound transmission. In timber construction, acoustic performance refers to how effectively the structure isolates airborne and impact noise between spaces, contributing to occupant comfort and compliance with building standards. Key factors influencing acoustic performance include material density, panel thickness, insulation, junction detailing, and floor/ceiling system design.

Working or applying force at a right angle (90°) to the natural alignment of wood fibres, which can significantly affect strength, appearance, and performance.

Forces or actions that are applied to a structure and must be considered in its design. In timber construction, action loads include dead loads (permanent/static, such as the weight of the structure itself), live loads (temporary/movable, like occupants or furniture), wind loads, snow loads, earthquake forces, and other environmental or accidental actions. Structural engineers assess these loads to ensure the safety, stability, and performance of timber buildings in accordance with the Australian Standards and the National Construction Code (NCC).

A substance used to bond two surfaces together.

The visual and sensory qualities of a material or structure that contribute to its overall attractiveness and design harmony. In timber construction, aesthetic appeal refers to the natural beauty, warmth, grain patterns, colour, and texture of wood, which can enhance both interior and exterior environments. It plays a key role in architectural design, influencing material selection and user experience.

A global framework developed by the United Nations to guide sustainable development at local, national, and global levels, addressing issues like deforestation, pollution, poverty, and urban growth.

The velocity of air in the passages between rows of boards in a rack.

Timber that is dried by exposure to air in a yard or shed, without artificial heat. See also: seasoning.

The direction parallel with the length of the fibres and other longitudinal elements of the wood.

A type of fastener used to attach structural or non-structural elements to concrete. It provides a secure, load-bearing connection between concrete and items like steel columns, timber posts, machinery, or framing systems.

Instrument for measuring the velocity of airflow.

Anisotropic materials have direction-dependent properties, meaning their mechanical or physical behavior changes based on the direction of the force or measurement.

Anti-kickback fingers are pivoting metal or hardened steel teeth that grip and hold timber as it's fed through a machine, allowing movement in one direction only and preventing reverse motion that could cause a dangerous kickback.

An anti-stain chemical is a fungicidal treatment used to protect green (unseasoned) timber from sapstain, bluestain, and mould growth, especially during the early stages after harvesting.

The classification of timber based on its visual characteristics, such as knots, grain, colour, and surface blemishes, rather than its structural strength. Appearance grading is used when timber is exposed in a finished application and aesthetics are a key consideration—such as in interior linings, flooring, or furniture. Grading rules vary by species and product type and are set out in relevant Australian Standards, ensuring consistency and quality in appearance-based applications.

A curved structure resting on supports at each end that supports loads primarily in compression.

The external corner or sharp edge formed where two surfaces or planes intersect, often seen along the edges of sawn or machined timber, stone, or concrete elements.

In the context of timber, construction, or sustainability, an attribute refers to a distinct characteristic or feature of a material, product, or process that can be used to describe, assess, or differentiate it.