The Sheet Metal and Air Conditioning Contractors’ National Association has released the fourth edition of its HVAC Duct Construction Standards – Metal and Flexible. Building on a history of duct construction standards nearly 100 years old, the updated 416-page standard was revised to provide contractors, designers and facility owners with the information needed 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
For more information, visit www.smacna.org/resources/technical/technical-standards.
