The Sheet Metal and Air Conditioning Contractors’ National Association Sheet Metal and Air Conditioning Contractors’ National Association (SMACNA), the leader in promoting quality and excellence in the sheet metal and air conditioning industry, recently announced the fourth edition of its HVAC Duct Construction Standards – Metal and Flexible is now available. Building on a history of duct construction standards nearly 100 years old, the Fourth Edition of SMACNA’s HVAC Duct Construction Standards – Metal and Flexible represents the state of the art in sheet metal duct fabrication and installation requirements.

As the sole American National Standards Institute (ANSI) accredited standard for fabrication and installation, the HVAC Duct Construction Standards – Metal and Flexible is the code-mandated standard for the industry. The updated 416-page standard was revised to provide contractors, designers, and facility owners with the information they need to apply effective and efficient solutions to their projects. Highlights of the updates to this standard include: 

• Added information on spray and aerosolized duct sealants
• Added tables for spiral flat oval duct for positive and negative pressure applications
• Added options for internal supports for spiral flat oval duct
• Updated liner requirements to include non-fiberglass liner types
• Added information for lined round duct and spiral fittings
• Added details for hangers to better illustrate where hangers are required
• Updated requirements for flex duct hanger spacing and hanger width, among other technical updates that will enable the standard to be fully compliant with industry advancements in sheet metal for air distribution systems

“The sheet metal and HVAC industry continues to evolve and adapt to new technologies and those changes are reflected in this new edition of the HVAC Duct Construction Standards. We’ve provided best-in-class information that allows code officials, design professionals and contractors to deliver safe, modern and resource-efficient constructed duct systems,” says Vince Sandusky, SMACNA’s CEO.

Technical standards and manuals developed by SMACNA members have worldwide acceptance by the construction and code community, as well as local and national government agencies. SMACNA standards and manuals address all facets of the sheet metal and HVAC industry – including duct construction and installation, indoor air quality, energy recovery, roofing and architectural sheet metal, welding, and commissioning – and advancements are made possible by those in the industry who provide suggestions for improvement based on knowledge, experience, and research. Materials, including the latest edition of the HVAC Duct Construction Standards – Metal and Flexible, are available to order in book or PDF format via SMACNA’s online bookstore.