Code Officials

Code Compliant Above Ground and Ground Contact Treated Wood

Above ground treated wood is code compliant for deck projects that are six inches or more from the ground. 

Above ground treated wood remains International Building Code (IBC®) and International Residential Code (IRC®) compliant for most deck projects under Section R317.1 and Section 2303.1.9 respectively.

Ecolife and Preserve - Exclusive Value-added Formulations


Ecolife - ABOVE GROUND Exposed Use (UC3B)
Exclusive formula for looks and longevity
    • No need to seal for up to three years
    • Reduces cracking and splitting up to 50%
    • Repels water for up to three years
    • Stabilized boards stay straighter
    • Protects against termites and fungal decay
    • Non-metallic wood preservative; less corrosive to fasteners
    • Perfect for deck joists, support beams, decking and railings 6” or greater above the ground
    • Can be used with a water-impermeable barrier for close ground installations

Preserve - GROUND Contact General Use (UC4A)
Proven lasting soil protection
  • All-purpose
  • Protects against termites and fungal decay
  • Penetrates deep into the wood for lasting performance
  • Ideal for residential, commercial and certain agricultural projects
  • Use for freshwater immersion and salt water spray application

The American Wood Protection Association Treated Wood Use Guide

As code officials are inspecting deck projects, they should be guided by the latest, most accurate information available. Above Ground treated wood remains IBC and IRC code compliant for most common decking applications under Section R317.1 and Section 2303.1.9 respectively.

Front of Treated Wood End Tag

Front of End Tags

To comply with the International Building Codes, pressure-treated wood bears the quality mark of an inspection agency that maintains the continuing supervision, testing and inspection over the quality of the treated wood.

Inspection agencies for treated wood are listed by an accreditation body that complies with the requirements of the American Lumber Standards Committee (ALSC) Treated Wood Program, or equivalent. The quality mark is required be on a stamp or label affixed to the treated wood, and shall include the following information:

  1. AWPA U1 – this shows the preservative is listed in the AWPA Standards
  2. AWPA (UCS) Use Category – Include BOTH Name and UCS Abbreviation Code
  3. Preservative code required. (EL2, ACQ, CA-C)
  4. Preservative Name Optional: Ecolife, Alkaline Copper Quaternary or Copper Azole Type C
  5. Preservative retention – the amount of preservative retained in the wood
  6. CheckMark and 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 “CheckMark” logo to make it easier to locate the agency logo.
  7. Manufacturer and Location – Name of treater and location of treating plant.

Optional Information:

  1. Year: Indicate year of treatment
  2. Lifetime Limited Warranty

Back of End Tags

Important Information:

  • California Prop 65 *
  • Fasteners and Connectors
  • Safety Information

* Required if sold into or used in California

CheckMark of Quality

CheckMark of Quality

Not all treated wood is the same. The key differentiator for code officials, architects, contractors, and homeowners is the end tag on the

lumber. The end tag should bear the distinctive CheckMark of Quality (pictured) as proof of ANSI-accredited, consensus-based AWPA standardization.

The CheckMark of Quality assures code officials, builders, and consumers that the preservative has been reviewed by the AWPA to meet stringent standards for superior deck life, performance, and environmental safety. The AWPA standards are directly referenced in the IBC® and IRC® model building codes.