Grease duct systems are intended for use in connecting Type 1 and 2 kitchen hoods, cooking ovens, and exhausting all commercial cooking appliances to the outdoors. All current NFPA 96 and International Mechanical Code editions now recognize UL 1978 Grease Duct as a safer alternative to field-fabricated steel systems. Jeremias grease ducts are available in single-wall, double-wall reduced clearance, and zero clearance options.
Single-wall is a direct replacement for field-fabricated steel. It may be field wrapped per NFPA 96 for reduced or zero clearance, eliminating welding in the field. If left unwrapped, it requires 18 inches of clearance to combustible materials.
Double-wall Reduced Clearance has 1.5” of ceramic fiber compressed into a 1.25” space between the inner liner and outer jacket. This results in a dramatically reduced clearance to combustible materials, and is perfect for single story buildings where the vent does not penetrate a fire-rated shaft assembly.
The special Double-wall Zero Clearance models utilize 3.25” of a unique higher density ceramic fiber insulation between the inner liner and outer jacket. These Zero Clearance models are also a two-hour fire-rated-resistant enclosure/duct assembly.
UL 1978 Standard, Grease Duct- under this listing, several Jeremias models have been determined suitable for Grease Ducts as determined by NFPA 96, the “Standard for Ventilation Control and Fire Protection of Commercial Cooking Operations”. UL confirmed proper minimum air space clearance to combustibles for 500°F continuous exhaust gas temperatures and 2000°F exhaust gas temperature for 30 minutes simulating a kitchen exhaust fire. UL also confirmed that the installed joints are grease and smoke tight.
UL 2221 - under this listing, the Jeremias ZC models have been determined suitable for Zero Clearance to combustibles and as a two-hour fire-rated-resistive enclosure assembly
See YouTube video of our Jeremias DWFL-ZC System vs. a field-fabricated and wrapped steel rectangular grease duct! Go to top of site page and click on YouTube logo.