Flexible Vinyl Duct
Flexible vinyl ducting should NEVER be used for dryer venting. They are a fire hazard!!
The packaging is clearly labeled:
* NOT FOR USE IN DRYER VENTING.
* RECOMMENDED FOR BATHROOM FAN VENTING.
Despite the warnings, many homes and town houses/condos we have seen many, the dryers were connected to vinyl ducting. Often the duct was partially melted by the heat from the dryer or simply ripped and disconnected.
Flexible Aluminum Duct
Flexible Aluminum Duct is constructed of aluminum and has a flexible design, making it a great choice for low- to medium-pressure, useful for venting clothes dryers and HVAC applications.
Semi-Rigid Duct is an accordion type of dryer vent that can be pulled out to the required length useful for venting clothes dryers, as an exhaust for bathroom fans, for venting kitchen range hoods and more it is flexible with a crimped end for easy installation (no joints, no elbows required) but the ribs slow down air flow considerably.
Sheet Metal Duct
This should be the preferred choice of dryer vent material for any home owner concerned with conserving energy and fire prevention. It’s highly recommended and/or required by Underwriters Laboratory (UL), the Association of Home Appliance Manufacturers, the Consumer Product Safety Commission, most (if not all) dryer manufacturers and most building codes .
The smooth surface prevents or slows down a possible lint build-up in the dryer vent, helps to achieve optimal airflow and reducing the operating temperatures of the dryer.