Information for Specifiers of Treated Wood Products
Engineers and architects, government agencies and others who develop and maintain project specifications which include the use of treated wood products have depended on AWPA Standards for well over 100 years because of its Technical Committees' expertise in the field of wood protection. Today, specifiers are faced with many different types of preservatives and species in the marketplace, so it is increasingly important for specifiers to continue to specify those products which meet AWPA Standards.
Why is it important to specify AWPA Standards?
A product specified in AWPA has been researched, evaluated and peer reviewed by the largest body of wood preservation/protection experts in North America. When a product has gone through our stringent ANSI accredited process, we believe they will perform well.
How do I specify treated wood products?
We have developed a simple two-page document which provides several examples of specifications for treated wood. Click here to download the document. It is a simple guide and is not intended to cover all possible uses. After reviewing the document, if you still have questions or need any assistance in developing your specifications, please contact us.
My specifications call for a number of AWPA C Standards, but those have been replaced by U1. How do I update my specifications?
Quite simple, really. All of the material specifications for treated wood products listed in all of the C standards are now found in a single AWPA Standard: U1. The simplest way to update your specifications is to replace all C standards with U1. If you wish to have more detail in your specs, such as restricting the wood to waterborne preservative treatment only, or you wish to determine the species and Use Category, you may add that as well. AWPA will be glad to assist you in updating your specs. Please contact us for any questions you may have.
How may I verify that materials on the jobsite comply with AWPA Standards?
Products that are compliant with AWPA standards will be have a clearly legible tag that states it is an AWPA Standardized product. In order to determine conformance with AWPA Standards, the end tag will contain the following elements:
AWPA U1 - this shows the applicable AWPA Standard
AWPA Use Category - examples are UC2, UC3B, or UC4A which describe the proper application for the treated wood product. The formal descriptions of the AWPA Use Categories are found in this excerpt from AWPA Standard U1.
Preservative name and/or code - examples are Copper Azole (CA-C), Inorganic Boron (SBX), Micronized Copper Azole (MCA) and many others.
Preservative retention - the nominal amount of preservative retained in the wood as specified in Standard U1, such as 0.060, 0.15, or 0.31, which varies by the type of preservative used
Inspection agency logo - if the treating plant subscribes to third-party quality control, you will see the logo of an agency accredited by the American Lumber Standard Committee and usually a "check-mark" logo to make it easier to locate the agency logo.
Manufacturer and Location - in the event you need a consumer information sheet or additional information on the product itself, this should help you locate the treating company
I have references to LP-2 and LP-22. What do they mean?
"LP-2" and "LP-22" were Inspection Procedures which had been used by the American Wood Preservers Bureau (AWPB) to determine the conformance of preservative treated wood products to certain Standards of the American Wood Protection Association (AWPA). AWPB ceased to exist on December 31, 1993. "AWPB LP-2" had often been used as a "shorthand" method of describing lumber and plywood which had been preservative treated with then-current waterborne preservatives to a retention of 0.25 pounds per cubic foot intended for above ground use. In a similar fashion "AWPB LP-22" had often been used to describe lumber and plywood treated with waterborne preservatives existing at that time to a retention of 0.40 pounds per cubic foot intended for soil and ground contact use. To use current AWPA Standards to specify the above described material the specifier should call for AWPA Standard U1. This Standard should be consulted to determine the species, preservative, and retention level combination which will provide similar protection to the finished product.
Is ACZA, CCA, and Creosote safe for use in marine environments?
The Western Wood Preservers Institute (WWPI) has developed models on the movement of wood preservatives from piling into marine environments. They have also sponsored numerous studies and have developed several publications, including "Treated Wood in Aquatic Environments Guide" and "Best Management Practices" for treated wood. WWPI also has several other informative publications on the WWPI Aquatics web page. Further information can be found in a USDA Forest Service study on preservative leaching in the marine environment.