Left unprotected, the warm 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 toner 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 exterior stain 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 semi-transparent stain or water repellent to the wood as soon as it is dry to the touch. 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.
*Note: if you wish to apply a paint or solid stain to MicroPro Sienna, ensure the wood is properly dry before applying. Using a light coloured paint or solid stain over the brown of MicroPro Sienna could be problematic. Using an exterior primer first could help with coverage. Follow the manufacturer’s instructions on how best to apply the product. We recommend applying the paint/stain to a small exposed test area before finishing the entire project to ensure it provides the intended result.
Recommendations from Finishing Product Manufacturers
For your convenience, listed below are product recommendations from some major manufactures of protective wood finishes to keep your MicroPro Sienna treated wood projects looking great:
NOTE: The links below are to third-party sites, which are not under the control of Timber Specialties or the MicroPro Sienna Treated Wood producers. Timber Specialties and the MicroPro Sienna Treated Wood producers do not monitor or review the content of third-party sites linked to this site and disclaim all responsibility for the operation and content of such sites.
Timber Specialties and the MicroPro Sienna Treated Wood producers make no claims about the performance of these products, nor do we guarantee, approve, or endorse the information or products available on these sites. We recommend that you follow the manufacturer’s instructions regarding when and how to apply the products.
Actual product colour may vary from colour shown in photos.
MicroPro Sienna Treated Wood products are produced by independently owned and operated wood preserving facilities.
MicroPro, MicroPro Sienna, and Cut-N-Seal are registered trademarks of Koppers Performance Chemicals Inc.