6.6003.1 Surface-Mounted Ducted

Topic: 
Exhaust
Subtopic: 
Fans
Desired Outcome: 
Surface-mounted ducted fans installed to specification
Note: 
The authority having jurisdiction may require that a licensed professional perform certain tasks outlined in this detail.
TitleSpecification(s)Objective(s)
6.6003.1a
Hole through interior surface

A hole no greater than a 1/4" greater than the assembly will be cut to accommodate fan assembly

Minimize repair work

Ensure a secure installation

6.6003.1b
Wiring

Wiring will be installed in accordance with original equipment manufacturer specifications, and local and national electrical and mechanical codes

Prevent an electrical hazard

6.6003.1c
Fan mounting

Fan outlet will be oriented toward the final termination location

Fan will be oriented so the equivalent length of the duct run is as short as possible

Fan will be mounted securely in accordance with manufacturer specifications

Ensure short duct run to achieve optimum air flow

Ensure a secure installation

Ensure fan housing does not shake, rattle, or hum when operating

6.6003.1d
Backdraft damper Backdraft damper A damper that allows air to flow in only one direction

A backdraft damper Backdraft damper A damper that allows air to flow in only one direction will be installed between the outlet side of the fan and the exterior

Prevent reverse air flow when the fan is off

6.6003.1e
Duct to fan connection

Duct-to-fan outlet will be connected and sealed as follows:

  • Round metal-to-metal or metal-to-PVC will be fastened with a minimum of three equally spaced screws
  • Other metal-to-metal or metal-to-PVC connections will be securely fastened and sealed with welds, gaskets, mastics (adhesives), mastic-plus-embedded-fabric systems, or tapes
  • Flexible duct-to-metal or flexible duct-to-PVC will be fastened with tie bands using a tie band Tie band A strap, often made of nylon, that mechanically squeezes a flexible duct to a fitting. Must have a minimum performance temperature rating of 165° (per UL 181A-type test) and a minimum tensile strength rating of 50 pounds tensioning tool
  • PVC-to-PVC materials will be fastened with approved PVC cement
  • Other specialized duct fittings will be fastened according to manufacturer specifications
  • In addition to mechanical fasteners, duct connections will be sealed with UL UL Underwriters Laboratories 181B or 181B-M listed material

Exhaust to outside

6.6003.1f
Fan housing seal

Gaps and holes in fan housing will be sealed with caulk or other sealants in accordance with manufacturer recommendations

Sealants will be compatible with their intended surfaces

Sealants will be continuous and meet fire barrier specifications

Prevent air leakage through fan housing

Ensure a permanent seal

Prevent a fire hazard

6.6003.1g
Fan to interior surface seal

Sealants will be compatible with their intended surfaces

Sealants will be continuous and meet fire barrier specifications

Prevent air leakage between house and fan

6.6003.1h
Air flow

Air flows in cubic feet per minute ( CFM CFM Cubic feet per minute ) will be measured and adjusted to meet the whole house upgrade design requirements

Exhaust sufficient air from desired locations to outside

6.6003.1i
Preventing air leakage caused by exhaust fans

Leakage to the house from other spaces will be prevented (e.g., garages, unconditioned crawl spaces, unconditioned attics)

Ensure occupant health and safety

6.6003.1j
Combustion safety

Pressure effects will be assessed and corrected on all combustion appliances

Ensure safe operation of combustion appliances

TitleSpecification(s)Objective(s)
6.6003.1a
Hole through interior surface

A hole no greater than a 1/4" greater than the assembly will be cut to accommodate fan assembly

Minimize repair work

Ensure a secure installation

6.6003.1b
Wiring

Wiring will be installed by a properly licensed contractor, as required by the authority having jurisdiction

Wiring will be installed in accordance with original equipment manufacturer specifications, and local and national electrical and mechanical codes

Prevent an electrical hazard

6.6003.1c
Fan mounting

Fan outlet will be oriented toward the final termination location

Fan will be oriented so the equivalent length of the duct run is as short as possible

Fan will be mounted securely in accordance with manufacturer specifications

Ensure short duct run to achieve optimum air flow

Ensure a secure installation

Ensure fan housing does not shake, rattle, or hum when operating

6.6003.1d
Backdraft damper Backdraft damper A damper that allows air to flow in only one direction

A backdraft damper Backdraft damper A damper that allows air to flow in only one direction will be installed between the outlet side of the fan and the exterior

Prevent reverse air flow when the fan is off

6.6003.1e
Duct-to-fan connection

Duct-to-fan outlet will be connected and sealed as follows:

  • Round metal-to-metal or metal-to-PVC connections will be fastened with a minimum of three equally spaced screws
  • Other metal-to-metal or metal-to-PVC connections will be securely fastened and sealed with welds, gaskets, mastics (adhesives), mastic-plus-embedded-fabric systems, or tapes
  • Flexible duct-to-metal or flexible duct-to-PVC connections will be fastened with tie bands using a tie band Tie band A strap, often made of nylon, that mechanically squeezes a flexible duct to a fitting. Must have a minimum performance temperature rating of 165° (per UL 181A-type test) and a minimum tensile strength rating of 50 pounds tensioning tool
  • PVC-to-PVC connections will be fastened with approved PVC cement
  • Other specialized duct fittings will be fastened according to manufacturer specifications
  • In addition to mechanical fasteners, duct connections will be sealed with UL UL Underwriters Laboratories 181B or 181B-M listed material

Exhaust to outside

6.6003.1f
Fan housing seal

Gaps and holes in fan housing will be sealed with caulk or other sealants in accordance with manufacturer recommendations

Sealants will be compatible with their intended surfaces

Sealants will be continuous and meet fire barrier specifications

Prevent air leakage through fan housing

Ensure a permanent seal

Prevent a fire hazard

6.6003.1g
Fan to interior surface seal

Sealants will be compatible with their intended surfaces

Sealants will be continuous and meet fire barrier specifications

Prevent air leakage between house and fan

6.6003.1h
Air flow

Air flows in cubic feet per minute ( CFM CFM Cubic feet per minute ) will be measured and adjusted to meet the whole house upgrade design requirements

Exhaust sufficient air from desired locations to outside

6.6003.1i
Preventing air leakage caused by exhaust fans

Leakage to the house from other spaces will be prevented (e.g., garages, unconditioned crawl spaces, unconditioned attics)

Ensure occupant health and safety

6.6003.1j
Combustion safety

Pressure effects will be assessed and corrected on all combustion appliances

Ensure safe operation of combustion appliances