Treated Timber & Landscaping

Timber treatments explained

The treatment used to protect pine depends on where and how the timber will be used. The most common outdoor treatments are copper chrome arsenate (CCA), alkaline copper quaternary (ACQ) and light organic solvent preservative (LOSP). A different strength of LOSP is used for internal applications such as house framing, along with H2F treatments such as bifenthrin.

Treatment end tags

End tags, burn brands and ink stamps show which treatment was used and the hazard level the timber is treated to.

Using CCA-treated timber

CCA-treated timber is suitable for all applications except domestic decking boards, handrails, children's play equipment, picnic tables and outdoor seating.

Important points about CCA

• All treated timber made by reputable companies and handled correctly is safe.
• CCA-treated timber has been used worldwide for more than 70 years without evidence of harm to health.
• After a two-year review, the government regulator (APVMA) found no compelling evidence of unacceptable risk to public health.
• There was no recommendation to remove existing CCA-treated structures.
• CCA remains approved for most outdoor uses, such as deck structures, pergolas, fencing, landscaping and vegetable gardens.
• As a precaution, the APVMA restricted CCA-treated timber in certain applications (listed above).

H2-F (blue pine framing)

H2 LOSP-treated timber has been used in Australia since the 1990s to protect house framing from termites. In 2004, pine manufacturers introduced a new treatment: blue pine framing, or H2-F. It offers:

• A more cost-effective option than H2 LOSP
• Better supply to meet growing demand for termite-resistant framing
• Suitability for internal framing only. It can't be used externally.
• A blue dye, so it's easy to tell apart from untreated framing
• Suitability for use south of the Tropic of Capricorn

Treatment hazard levels