Our site is currently being updated and pages are changing regularly. We thank you for your patience during this transition and hope that you find our new site easy to use.

Construction timbers in Queensland

'Construction timbers in Queensland' describes how to use different timbers in Queensland.

It describes the properties of timbers used in the construction of Class 1 to Class 10 buildings (e.g. houses, carports, garages, greenhouses and sheds) in Queensland, as well as other purposes such as furniture, landscaping and outdoor structures (e.g. playgrounds, fences).

It also recommends appropriate uses of timbers across the state.

This publication is a primary reference document in the Queensland variations to the Building Code of Australia (BCA, Australian Building Codes Board) under the Queensland Building Act 1975.

The publication has two books.

Book 1 provides definitions and descriptions of timber properties and explains design life, building applications and decay hazard zones, which support the information given in Book 2.

Book 2 provides reference tables for the properties, target design life and conditions for using in 50+ building applications across Queensland for more that 600 Australian and imported timbers.

About this 2017 edition

Cite the publication as:

Construction timbers in Queensland: properties and specifications for satisfactory performance of construction timbers in Queensland - Class 1 and Class 10 buildings', books 1 and 2 (2017) Queensland Government.

Its short title is: CTIQ 1 and 2.


  1. 2013, 1st June Book 2, Index number 531,Mastixiodendron pachyclados (garo garo, origin PNG) natural durability ratings revised to: Above-ground (4); In-ground (4).
  2. 2017, 15th August.
  3. 2.1. Book 1. Definitions and descriptions: Target design life: 50 years; Environment: In-ground; conditions of use, point 4 revised to: ‘Timbers classed as In-ground durability class 3 and 4 and that are coded H5 are suitable for these uses (TDL 50 years, in-ground), if preservative treated to H5 level in accordance with AS 1604, and may contain limited amounts of unpenetrated or inadequately treated heartwood not comprising more than 20% of the cross-section of the piece at any point.’

    2.2. Book 1. Definitions of H level, H3, H4 & H5 added text: N.B. Currently, the heartwood of most hardwood timbers and some softwood timbers cannot be treated to H3, H4 or H5 level of protection. The timber treater is to ensure that their process has achieved the required level of penetration to meet the stated H level specification.

    2.3. Book 2. Added timber, properties and conditions for use: Index number 608, cumaru (Dipteryx odorata).

    2.4. Book 2. Name change: Eucalyptus viminalis standard trade name changed to gum, manna (from gum, ribbon, rough-barked).

Get a copy of the publication