SR​ Subduct Riser​ 10” diameter​ Up to​ Up To
MORE INFO 52% Free Area​ Patented​

vs Conventional Subducts​
ABOUT The SR from LFSystems is a low-profile Subduct Riser made of 26-gauge galvanized steel. The SR is beneficial in applications where a 22 inch subduct riser is necessary to maintain the fire and smoke rating of an exhaust shaft; instead of using fire and smoke dampers. The SR is IBC 2012 compliant for bathroom, kitchen, and clothes dryer exhaust shafts. The SR is available with female vent connections of 4 and 6 inches. ​

​Surrounded by a 3/8 inch flange, the SR attaches firmly to the inside wall of the main shaft, eliminating the possibility of loose or disconnected risers. The SR provides the minimum 22 inch rise while maintaining a low profile within the main exhaust shaft. Using SR risers as an alternative to conventional field-erected sub-ducts results in lower velocities and less restriction in the main shaft. This allows for smaller main shafts with less generated noise.