Subduct Riser Manufacturing provides low-profile subduct risers made of 26 gauge galvanized steel, specifically designed for applications requiring a 22 inch subduct riser to maintain the fire and smoke rating of an exhaust shaft instead of using fire and smoke dampers. Our low-profile subduct riser, model LSR, is compliant with the International Building Code (IBC) and International Mechanical Code (IMC) for bathroom, kitchen, and clothes dryer exhaust shafts.

 

The LSR is available with female inlet connections of 4, 5, 6, 8, and 10 inches, providing versatility for various applications including bathroom exhaust and residential kitchen hood exhaust. The riser is surrounded by a 3/8 inch flange, ensuring a secure attachment to the inside wall of the exhaust shaft, eliminating the risk of loose or disconnected risers. The LSR offers the required 22 inch rise while maintaining a low profile. 

 

Utilizing LSR risers as an alternative to conventional field-erected subducts result in lower velocities and reduced restriction in the main exhaust shaft. This allows for smaller main shafts, ultimately leading to less generated noise as well.