CCA

Key Benefits of Wolmanized® Heavy-Duty™ Pressure Treated Wood

• Protection against fungal decay, rot, and termites

• Easy to work with, repair, and modify

• Strong, versatile, economical, and resilient

• Successful track record for over 80 years

Best Applications for Wolmanized® Heavy-Duty™ Treated Wood 

Wolmanized® Heavy-Duty™ wood is best for applications where timbers are in contact with water, soil, concrete or masonry that can be subject to periodic wetting or exposed to moisture or high humidity. These conditions are condusive to termite infestation and the growth of fungi. Wolmanized® Heavy-Duty™  wood is suitable for: 

• Piling 

• Poles, building & utility 

• Plywood 

• Highway guard & sign posts 

• Agricultural fence posts 

• Lumber for saltwater use 

• Marine construction 

• Permanent Wood Foundations 

• Sawn structural timbers 

• Sawn crossarms 

• Structural glued laminated members 

• Structural composite lumber 

• Shakes & shingles 

• Roller coasters 

• Cooling towers 

*For residential and other applications requiring a copper-based preservative, see Wolmanized® Residential Outdoor Wood / CA-C 

Safe Use & Handling of Wolmanized® Heavy-Duty™ Treated Lumber 

After the treatment process, Wolmanized® Heavy-Duty™ wood undergoes a fixation stage that locks the preservative into the wood fibers, making it resistant to leaching and safe for both users and the environment when used as directed. Backed by over 70 years of use, its safety for people, pets, plants, and ecosystems has been supported by research from both academic institutions and government agencies. 
As a registered pesticide, Wolmanac® CCA preservative is subject to regular review by the Environmental Protection Agency (EPA). The EPA, along with other regulatory bodies, oversees its manufacture, transportation, and application. Safety data sheets (SDS) are available from licensed treatment facilities producing Wolmanized® Heavy Duty™ wood. 

AWPA Standards & Building Code Requirements

The American Wood Protection Association (AWPA), a non-profit organization which promulgates voluntary wood preservation standards, developed a Use Category system that classifies treated wood based on its intended exposure and service conditions rather than by specific wood products. This system helps simplify selection for both professionals and consumers. Since most building codes now reference AWPA standards, the Use Category system is gradually replacing the older Commodity-based classifications in construction codes. 

Best Management Practices (BMPs) For Treated Wood Preservation

The Western Wood Preservers Institute, in conjunction with industry representatives, users, and scientists, developed BMPs to help ensure fixation of preservative chemical in treated wood prior to shipment. In the fixation process, some preservative components bond to the wood while others form insoluble precipitates. Specification of BMPs results in wood with a very high percentage of fixed preservative and may also reduce shipping weight. 

Why Incising Improves Preservative Penetration in Certain Species of Treated Wood 

In many western species, penetration improvement methods are employed to improve the depth and uniformity of preservative penetration into wood. Most commonly this is seen as a pattern of slits ("incisions") on the surface of lumber. Full-length incising and deep-incising are other methods, as are radial-drilling and through-boring, used mostly for poles and piling.

Although these methods can improve preservation, they can result in a strength reduction for the wood, depending on the pattern, size, and number of incisions. When treated sawn wood products have been incised, the reference design values must be multiplied by the incising factor, Ci, in accordance with section 4.3.8 of the National Design Specification for Wood Construction. A review of penetration improvement methods is recommended before insertion into a specification.

NOTE: Incising is required by the AWPA Standards for refractory species. DF is a refractory species with up to 75 % heartwood.

What "Treated to Refusal" Means for Wood Performance and Code Compliance

This phrase — Treated to Refusal — indicates that the wood was treated under specific conditions until it refused additional preservative, a point usually below the requirements of industry standards. The result is wood that cannot be relied upon to last as long as wood that meets standards. Such wood does not comply with model building code requirements for treated wood. 

To assure yourself of properly treated wood, look for the logo of an ALSC-accredited inspection agency on lumber tags or ink stamps. The logo often appears beside a Checkmark symbol.

Hardware Recommendations for Treated Wood Installations

Environments that encourage fungal decay and termite activity also tend to accelerate the corrosion of metal. To help prevent this, it’s recommended to use hot-dipped galvanized fasteners that comply with ASTM A153 and connectors made from ASTM A653 Class G185 sheet metal, or higher-grade options. For Permanent Wood Foundation applications, 304 or 316 stainless steel is preferred. Aluminum should not be placed in direct contact with treated wood.

Suitable Wood Species for Wolmanac® CCA Preservative

The American Wood Protection Association (AWPA) recognizes that a variety of wood species can be treated with Wolmanizac® CCA preservative. However, achieving the required levels of preservative penetration and retention can be challenging in certain species. When wood is described as “treated to refusal,” it means the material has absorbed as much preservative as it can, though it may still fall short of meeting AWPA standards or providing reliable protection. 
Species suitable for treatment include: 

• Southern Pine Group 

• Ponderosa Pine 

• Red Pine 

• Western Red Cedar 

• Hem-Fir Group* 

• Jack Pine* 

• Lodgepole Pine* 

• Sugar Pine* 

• White Pine* 

• Radiata Pine 

• Caribbean Pine 

• Coastal Douglas Fir* 

• Western Larch* 

• Redwood* 

• Sitka Spruce* 

For certain species marked with an asterisk, incising, the process of making small, surface-level cuts, is necessary to allow better preservative absorption.