New Technical Resource Bulletin (TRB)

From the Technical Resources Department. Update to the SMACNA HVAC Duct Construction Standards, Metal and Flexible, Fourth Edition, Figure 2-18 Corner Closures - Flanges.

This technical resources bulletin updates the language for corner fastening requirements used in conjunction with the T-25a and T-25b flanged transverse joint assembly.

TRB #01-25 Figure 2-18 Corner Closures - Flanges

Nov 24, 2025 — Member Update

Latest Articles

Kitchen Ventilation Systems and Food Service Equipment, 2nd Edition Now Available

Aug 26, 2026 - Second edition builds upon the first edition and continues to serve as a basic reference guide to industry-accepted practices for the fabrication and installation of commercial kitchen ventilation systems.

Longtime CAL SMACNA Leader Cyndi Marshall Passes Away

Aug 26, 2026 - Former CAL SMACNA Executive Vice President was a trailblazer in the industry, serving as a coalition builder throughout the trades over the course of an impactful 30-year career.

Learn More About the Identify Function for Cybersecurity

Aug 26, 2026 - Article in SMACNA’s Cybersecurity Series Dives into the foundational aspect of any data protection plan.

smacnalogo__185_287__with_white_3a5897_outline