Durable Construction with Preservative-Treated Wood

This course is no longer active
Sponsored by Western Wood Preservers Institute

Learning Objectives:

  1. Discover how preservative-treated lumber is manufactured, the steps taken to assure proper quality control and the safety and effectiveness of preservative used today.
  2. Learn how to properly specify pressure-treated wood products using the American Wood Protection Association's Use Category System.
  3. Explain Western Wood Preservers Institute’s Best Management Practices to safeguard the use of preserved wood and minimize any impacts on aquatic and other sensitive environments.
  4. Define how to utilize approved environmental assessment tools to evaluate the impacts of the use of preservative-treated wood in aquatic and sensitive environments.


AAA 1 Structured Learning Hour
This course can be self-reported to the AANB, as per their CE Guidelines
AAPEI 1 Structured Learning Hour
MAA 1 Structured Learning Hour
This course can be self-reported to the NLAA.
This course can be self-reported to the NSAA
NWTAA 1 Structured Learning Hour
OAA 1 Learning Hour
SAA 1 Hour of Core Learning
This course can be self-reported to the AIBC, as per their CE Guidelines.
This course is approved as a Structured Course
This course can be self-reported to the AANB, as per their CE Guidelines
Approved for structured learning
Approved for Core Learning
This course can be self-reported to the NLAA
Course may qualify for Learning Hours with NWTAA
Course eligible for OAA Learning Hours
This course is approved as a core course
This course can be self-reported for Learning Units to the Architectural Institute of British Columbia

In applications where wood may be exposed to moisture, insects or fungal organisms, preservative-treated wood can help ensure a building’s durability. In this presentation, participants will learn about the manufacturing process for pressure-treated wood, available products and their differences, and how preserved wood is used in construction.

Topics include an overview of preservative treatments, desired service life and exposure conditions, AWPA Use Category standards and current issues concerning the safe use of treated wood. Participants will also receive instructions for free downloading of the Treated Lumber Guide smartphone/tablet app.

This presentation is presented by Butch Bernhardt, senior program manager for Western Wood Preservers Institute (WWPI) in Vancouver, Wash. Butch has provided product support and education on wood products for nearly three decades. His responsibilities at WWPI include product education, technical support, standards, distance learning and digital specification tools for preserved wood products. He has presented at conferences for international, national and regional groups. A graduate of Oregon State University, Butch is the third generation in his family to work in the wood products industry.

Durable Construction

Photo courtesy of Western Wood Preservers Institute

Preservative treating protects wood that is exposed in the outdoors, offering a durable and long-lasting service life. A variety of preserved wood products are available today, from decking and fencing to bridge timbers and building posts.


Western Wood Preservers Institute Western Wood Preservers Institute (WWPI) is a nonprofit member trade organization representing the interests of the preserved wood products industry throughout western North America for more than 70 years. WWPI is responsible for supporting the safe and proper use of preservative-treated wood products in construction through education and technical support.


Originally published in June 2021