The online home for Western Wood Preservers Institute

Welcome to the Western Wood Preservers Institute website. Since 1947, WWPI has represented the interests of the preserved wood products industry throughout western North America. The membership consists of companies that either manufacture products, are directly affiliated or provide a service to the preserved wood industry.

Our site includes information on all services WWPI delivers to its members and those specifying and using preserved wood products. You can also review the Institute's current membership and links to other sites in the wood preserving industry.

Information on preserved wood products, including our Technical Library and digital specification tools, is now available on our sister website

Learn more about fire-retardant-treated wood products at Explore key information on treated wood utility poles at

For those in the state of California, you can get guidance on disposing of Treated Wood Waste (TWW) on our newest website

If you have any questions or suggestions on how we can further improve this site, please use the Contact Us form and send us your comments.

What's New

Here's what's happening at WWPI:

MEMBERS ONLY! The 2023 Winter Meeting is set for Feb. 22-23 in San Diego, Calif. Get more details in the Members Only section.

Check out the new WWPI online eUniversity with courses on preserved wood and fire retardant wood which qualify for Continuing Education Units (CEUs). Both self-guided and narrated versions of each course are available.

See the online Environmental Assessment Model to assess potential impacts of using preserved wood in or above water.

Watch how preserved wood is made and its many uses where durability and long service life is required.

MEMBERS ONLY! Review the exclusive Quality Control Education Section with training modules for in-plant quality control. The training materials can be used for individual training or for group sessions. See more details in the Members Only section.

Visit the Preserved Wood Online Tech Library for up to date information and recommendations.

Looking for preserved wood? Check out the Sources of Supply publication in the exclusive Preserved Wood Technical Library.

Catch up on current news on our Facebook and Pinterest pages.

Explore all things related to preserved wood utility poles on the website.

What we do

WWPI works on behalf of its members to increase public understanding and confidence in preserved wood products and secure reasonable and economic regulations regarding the production and use of these products. Guided by an active membership, the Institute's services are provided for the following product groups or issues:

The Institute is a non-profit organization supported through the financial contributions from three membership groups:

  • Treater Members - companies who operate facilities that pressure treat wood products
  • Supporting Members - companies directly affiliated with the industry through supplying preservatives or engaged in major wood products wholesaling
  • Associate Members - companies providing services or deriving benefits from the wood preserving industry

For more information on WWPI services and membership, please use the navigation bar at the top of this page to go to the respective section. To contact WWPI, please click on the Resources link and select Contact Us.

Members Only

Open only to Treater, Associate and Supporting Members. If you do not have a password, contact WWPI.

Wood questions? Get answers!


Everything you need to know about Western preserved wood is just a click away with the new website

Discover how wood is preserved by using pressure to infuse preservatives into the wood fiber. Explore the preservatives used today which are safe for people and the environment and offer durability and long-lasting performance. See the variety of ways preserved wood can be used in residential, commercial and industrial applications.

The website features an exclusive Preserved Wood Technical Library, offering an extensive collection of downloadable publications, technical sheets and design tools to properly select, specify and use Western preserved wood for almost any project.

>>Check out today!

See the hottest new site
on fire retardant wood


Learn how wood is protected from fire through pressure treating with fire retardants in the new, full-featured website

Explore how fire retardant wood products are made and how they work to protect structures against fire. Discover the advantages of pressure treating vs. surface coatings and find out more about the interior and exterior fire retardant treatments used by Western manufacturers today.

>>Take a look at today!