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There are important steps to consider when working with MicroPro Sienna treated products.

Safe Practices

  • Wear gloves when working with wood.
  • Only treated wood that is visibly clean and free of surface residue should be used.
  • Some preservative and/or pigment colour may migrate from the treated wood into soil, water or other surfaces. It may also dislodge from the treated wood surface upon contact with skin. Wash exposed skin areas thoroughly.
  • Wash exposed skin areas thoroughly. Wash work clothes separately from other household clothing before reuse.


MicroPro Sienna® Treated Wood with MicroPro technology exhibits corrosion rates on metal products similar to untreated wood.

For interior or exterior applications, use fasteners and hardware that are in compliance with the manufacturer's recommendations and the building standards for their intended use. As with any good design and construction practices, MicroPro Sienna Treated Wood should not be used in applications where trapped moisture or water can occur. Where design and/or actual conditions allow for constant, repetitive or long periods of wet conditions, only stainless steel fasteners should be used.

For exterior applications:

The following minimum galvanization levels may be used for connectors, joist hangers, fasteners and other hardware that are placed in direct contact with exterior applications of treated wood which utilizes MicroPro technology:

  • Fasteners - nails, screws, See our Australian hardware brochure
  • Hardware - connectors, joist hangers
  • The effects of other building materials within a given assembly, along with environmental factors, should also be considered when selecting the appropriate hardware and fasteners to use for a given project containing treated wood.
  • Stainless steel fasteners and hardware are recommended for use with treated wood in other severe exterior applications such as swimming pools, salt water exposure


Left unprotected, the warm red-brown colour of Sienna will fade to a soft tan or beige and transition to grey over time. The length of time will vary according to the exposure to sunlight, the wood species and the application. This transition can be slowed by application of a semi-transparent stain or a water repellent with added colour after installation to provide resistance to weathering and UV exposure.

Apply a weather resistant finish

Any exposed wood, pressure treated or not, should be protected with a high quality water repellent finish or stain with water repellent to help reduce warping, checking, and splitting. The application of a clear water repellent will allow the colour of the wood to naturally fade over time. The addition of pigments or colour in a stain/finishing product help to protect the wood surface from UV damage and colour fading.

If you desire to apply a paint, stain, clear water repellent, or other finish to your preservative treated wood, we recommend following the manufacturer's instructions and label of the finishing product. Unless the manufacturer stipulates otherwise, you can apply a stain or water repellent to the wood as soon as it is dry to the touch, which may be as soon as two weeks or as long as eight. It will depend on weather, the exposure to sunlight and how wet the wood was when it was installed (it is saturated with water during pressure treatment). To test that the treated wood is surface dry, sprinkle water droplets on the surface. If the water droplets are absorbed into the wood, it is ready for stain. If not, try sprinkling again in a few days.

If you want to restore the weathered product to the original Sienna brown colour, we suggest purchasing a semi-transparent water repellent stain that closely matches the original Sienna brown colour. Before you start, we recommend you apply the finishing product to a small exposed test area before finishing the entire project to insure it provides the intended result before proceeding.

Application of a Remedial Preservative

As with all outdoor treated timber products, where MicroPro Sienna is cut, notched, drilled or rebated the exposed areas should be resealed with a suitable remedial preservative such as Protim Solignum CN oil to ensure a treatment envelope for durability against fungal and termite attack is maintained. Note that while CN oil has a green colour on initial application this colour will change to a brown colour after a few weeks of sun exposure. A clear preservative such as Protim Solginum XJ may also be used for non-ground contact applications.


  • All sawdust and construction debris should be cleaned up and disposed of after construction.
  • Do not burn treated wood.
  • Do not use treated wood as mulch.
  • Users should dispose of treated wood scraps and cut offs in accordance with relevant disposal regulations. In general small quantities of treated wood waste may be disposed of in general domestic waste.


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