Dryer Vent Checklist
 

- Dryer duct must be at least 4" diameter and as large as dryer outlet.

- Concealed ducts must be rigid metal (galvanized or aluminum) duct.

- Duct joints shall be secured with metal tape, do not use screws or rivets.

- Unless otherwise permitted by dryer manufacturer, developed length of dryer
  duct shall not exceed 25 feet. A 45 degree elbow counts as 2 ½ feet of pipe
  and a 90 degree elbow counts as 5 feet of pipe.

- Joints shall be installed so the male end of the pipe points in the direction
  of the airflow (away from the dryer) See figure 1 below.

- Dryer vents shall be independent of all other systems and terminate outdoors.
  (Do not vent into another chimney or vent)
- Outside termination hood should be equipped with a back draft damper.

- Duct backpressure should not exceed 0.6 WC (inches of water column). 
  Higher backpressures indicate a poorly installed vent.

- Use flexible metal connectors between the dryer and the duct.
  Plastic connector ducting is not recommended.

 

The recommendations shown above are based on dryer vent manufacturer’s information and local building code requirements. Consult your dryer installation manual for exact requirements for your dryer.