Factory-listed grease duct system
Modular kitchen exhaust
The approved design, adopted code, qualified procedure, and exact manufacturer instructions control this installation.
Before you start
- Grease duct is a fire/life-safety system. Verify the approved design, adopted code, hood and fan requirements, listed enclosure or shaft details, and inspection hold points before fabrication or installation.
- Obtain the exact manufacturer installation instructions and approved submittal for the listed grease-duct system on the project.
- Confirm every section, band, gasket, sealant, support, adapter, access component, and enclosure part belongs to the same approved system.
- Inspect gaskets, male and female ends, locking features, witness marks, labels, and factory insulation or outer shells for damage.
- Do not substitute hardware or combine parts from different manufacturers or product families.
Tools and materials
The exact listed grease-duct components, manufacturer-specified gasket or sealant, joint bands and locking hardware, listed supports and fire-rated enclosure components, torque or hand tools specified by the manufacturer, tape, marker, level, soft lifting equipment, and the current installation manual.
Lay it out
- Lay out the route, support locations, access components, cleanout path, expansion or movement components, roof and hood adapters, and required enclosure clearances.
- Orient sections according to the manufacturer flow direction, female/male end, drain direction, or label requirements.
- Keep factory labels and inspection markings visible where the listing or inspector requires them.
Set and support it
- Install only the listed support types at the approved locations and spacing.
- Support each assembly before closing the next joint so bands and gaskets are not carrying dead load.
- Use the manufacturer's handling method to protect factory insulation, outer shells, and joint ends.
Make the connection
- 1
Read the joint sequence for the exact model before assembling the first connection.
- 2
Clean and inspect both mating ends and replace any damaged gasket or component.
- 3
Apply only the specified sealant, in the specified location and amount, when required.
- 4
Seat the sections fully to the manufacturer's stop, witness mark, or engagement requirement.
- 5
Install the exact joint band, clamp, locking ring, or hardware in the required orientation.
- 6
Tighten or lock the joint using the manufacturer's sequence and specified tool method.
- 7
Install listed support, insulation, outer casing, firestop, or enclosure components in the required order.
- 8
Document the joint and keep labels available for inspection.
Check the install
- Every connection is fully seated, locked, and assembled exactly as the listed instructions show.
- Gaskets are undamaged and not pinched or displaced.
- No unlisted fastener, sealant, adapter, or mixed-system part is present.
- Supports and enclosure components match the approved system.
- Labels, access points, and inspection features remain visible and usable.
Common mistakes
- Assuming all factory-built grease duct connects the same way.
- Mixing bands, adapters, gaskets, or supports from another listed system.
- Adding extra screws or sealant that the listing does not permit.
- Covering labels and joint features before inspection.
Stop and ask
Stop immediately if the installation instructions are unavailable, parts from different systems are mixed, a listed component is damaged or missing, or the field condition requires a connection not shown in the approved manufacturer system.