Install a Bathroom Exhaust Fan and Vent Duct

A. Finished-Project Specification

Quantity: one listed exhaust fan installed at the approved ceiling location, one dedicated sealed and supported duct connecting the fan collar to one listed exterior termination with backdraft damper, completed electrical connection within the approved scope, and a completed installation and test record.

B. Component Schedule

Component	Quantity	Material	Finished Size	Preparation
Exhaust fan housing and motor assembly	1	Listed per approved design	Per manufacturer rough-opening dimension	Verified fan and sound rating match design before mounting
Dedicated exhaust duct	Per approved route length	Listed rigid, semi-rigid, or insulated flexible duct per design	Diameter per design; length per measured route	Cut square; inner liner and jacket prepared per Chapter 10 method where flexible duct is used
Exterior termination with backdraft damper	1	Listed per approved design	Per manufacturer opening dimension	Verified compatible with duct diameter and wall or roof assembly
Duct clamps or listed closure	Per joint	Listed per duct system	Sized to duct diameter	Installed per manufacturer torque or engagement specification
Flashing and sealant	Per opening	Compatible with roofing or siding assembly	Per manufacturer coverage requirement	Integrated in shingle-lap order with the building envelope

C. Material Takeoff

• Fan and termination: one listed exhaust fan matching the approved rating and sound rating; one listed exterior termination with backdraft damper and, where permitted, pest screen.
• Duct materials: dedicated duct sized to the approved diameter, sufficient length for the measured route with the specified support interval, mastic or listed tape for every joint, insulation where required to control condensation.
• Fasteners and hardware: housing support fasteners specified by the fan manufacturer, duct clamps or listed closures per joint, flashing fasteners compatible with the roofing or siding assembly.
• Electrical materials: wiring devices and connectors specified by the approved electrical scope.

D. Fastener and Hardware Schedule

Joint	Fastener/Hardware	Installation Requirement
Housing to framing or support bracket	Manufacturer-specified fastener	Installed per manufacturer instructions; housing level and stable before duct connection
Duct to fan collar	Listed clamp or draw band	Full engagement over collar; sealed with mastic or listed tape
Duct to termination collar	Listed clamp or draw band	Full engagement over collar; sealed with mastic or listed tape
Termination to wall or roof assembly	Manufacturer-specified fastener	Installed with flashing integrated in shingle-lap order and sealant applied per manufacturer instructions
Duct supports along the route	Wide approved strap	Installed at the manufacturer-specified interval without compressing insulation or creating sag

E. Acceptance Standards

Check	Standard
Fan and duct match	Installed fan rating, sound rating, and duct diameter match the approved ventilation design exactly
Housing mounting	Housing level, secure, and supported per manufacturer instructions
Duct route	Dedicated to this fan only; shortest approved path; bends and equivalent length within the manufacturer limit
Duct sealing and support	Every joint sealed with mastic or listed tape; supports at the specified interval without sag or crushing
Termination	Listed termination with functioning backdraft damper, discharging directly outdoors, flashed in shingle-lap order
Electrical connection	Completed within the approved electrical scope; circuit verified de-energized before work and functional after restoration
Operating test	Fan starts, damper opens, exterior discharge confirmed, no abnormal noise or vibration

F. Preparation and Design Confirmation

1. Review the approved ventilation design, fan rating, sound rating, duct size, route, termination, electrical circuit, controls, clearances, and permit requirements. Record each value on the Ventilation Design Record before proceeding.
2. Confirm that required ventilation calculations and fan selection have been completed by the approved design authority. Do not select or substitute the fan rating, duct size, or termination independently.
3. Verify ceiling framing, insulation, vapor control, roof or wall assembly, and access route. Use the stud finder and visual inspection from both sides of the ceiling where accessible.
4. Confirm that the fan is listed for the intended location, including tub or shower zones where applicable. Check the fan's listing label against the installation location before mounting.

G. Electrical Isolation and Layout

1. De-energize the assigned electrical circuit and verify safe conditions. Use the Chapter 2 shutdown, lockout, and voltage-verification procedure at the assigned breaker.
2. Mark the fan centerline and rough opening from the approved room layout. Use the tape measure and the manufacturer's rough-opening dimension.
3. Inspect both sides of the ceiling for framing, wiring, plumbing, ducts, and hazards. Confirm the planned opening avoids joists, wiring, and plumbing not part of this project.

H. Housing Installation

1. Cut the ceiling opening without damaging structural members or utilities. Cut to the exact rough-opening dimension using the drywall saw or hole saw.
2. Install the housing support brackets or framing in accordance with the fan instructions. Use the fasteners specified in the Fastener and Hardware Schedule.
3. Set the housing at the correct relationship to the future ceiling finish. Confirm the housing depth matches the manufacturer's finished-ceiling reference.
4. Secure the housing and verify it is level and stable. Check level in two directions before proceeding to duct connection.

I. Duct Routing and Connection

1. Route the listed exhaust duct by the shortest approved path. Confirm the route matches the approved design before cutting duct material.
2. Minimize bends and preserve the required duct diameter. Do not reduce the duct diameter at any point along the route.
3. Support the duct without sagging, crushing, or contact with damaging surfaces. Install wide approved straps at the manufacturer-specified interval.
4. Connect the duct to the fan collar using the specified clamp and seal. Seat the clamp fully and seal the joint with mastic or listed tape.
5. Insulate the duct where required to control condensation. Apply insulation using the Chapter 7 method where the duct passes through unconditioned space.

J. Exterior Termination and Flashing

1. Prepare the exterior opening using the approved roof or wall procedure. Confirm the opening dimension matches the termination's manufacturer specification.
2. Install the listed termination with backdraft damper and pest screen only where permitted. Verify the damper moves freely before final fastening.
3. Integrate the termination flashing with roofing or the weather-resistive barrier in shingle-lap order. Confirm each upper layer overlaps the layer below it.
4. Do not terminate into an attic, soffit, crawlspace, garage, or wall cavity. Confirm the termination discharges directly to the exterior before sealing the opening.

K. Electrical Completion and Air Sealing

1. Complete the electrical wiring under the approved electrical scope. Connect conductors per the fan manufacturer's terminal instructions and the approved circuit design.
2. Air-seal the fan housing to the ceiling air barrier without blocking service or drainage features. Use a compatible sealant that does not obstruct the damper or service access.
3. Install the grille. Confirm the grille seats fully and does not obstruct airflow.

L. Testing, Inspection, and Documentation

1. Complete required inspection before concealment and energization. Do not close the ceiling or energize the circuit until the required inspection has passed.
2. Restore power and operate the fan. Restore the assigned breaker and start the fan using its control.
3. Verify damper opening, exterior discharge, sound, vibration, and grille draw using the approved test. Confirm the backdraft damper opens fully and air discharges directly outdoors.
4. Stop for backdraft, duct leakage, water intrusion, excessive noise, or failed operation. De-energize the circuit before making any correction.
5. Document fan, duct, termination, electrical handoff, and test results. Complete every field on the Inspection Checklist before closeout.