Lowe's, Home Depot and Ace Hardware sell replacement dryer vent pipe. When replacing dryer vents, using smooth, rigid 4-inch pipe helps to prevent lint clogs and speed drying of clothes. Owners should replace any flexible plastic or aluminum foil type vents.
When replacing dryer vent pipe, homeowners should consider the length of the vent. For safety, the maximum vent length is 25 feet. If the vent makes 90-degree turns, the owner should reduce the maximum length by 5 feet for every turn. If the existing pipe exceeds these lengths, the owner should consider rerouting the vent when replacing the pipe.
Dryer vents should always lead outside the home. Venting to the inside or attic causes moisture problems and allows flammable lint to collect in the house. A dryer vent cap allows the machine to vent while preventing pests and cold air from entering the vent.
Lint collecting in dryer vents creates a fire hazard and makes the machines less effective at drying clothes. Lint usually begins collecting on the screen or louvers of the vent cap. This collection slows the air exiting the machine. The reduction in airspeed allows lint to fall into the vent before it has a chance to exit it, increasing the lint buildup.