Since the shift from CCA-treated woods, numerous alternative treatments not covered in Simpson Strong-Tie's Preservative Treated Wood Technical Bulletin have been introduced into the marketplace. In order to understand the corrosive nature of some of these treatments, Simpson Strong-Tie has reviewed the chemical treatment supplier third party corrosion test results to determine the appropriate minimum fastener and connector recommendation. Click on the links below to read the joint recommendation letter between the treatment chemical supplier and Simpson Strong-Tie.

• Joint recommendation letter for Sustain™ preserved wood
• Joint recommendation letter for Arch Chemicals Dispersed Copper Azole Type C (µCA-C)