What is the minimum diameter required for a clothes dryer exhaust duct?

The minimum diameter required for a clothes dryer exhaust duct is 4 inches. This specification helps ensure that the venting system can efficiently expel moist air, heat, and lint produced during the drying process. A larger diameter allows for better airflow, reducing the risk of lint build-up, which can lead to lint blockages, increased drying times, and potentially hazardous situations such as dryer fires. This standard is established by building codes and safety regulations to promote safe and effective operation of clothes dryers.

Inadequate duct size can impair the dryer’s efficiency and increase energy consumption, as the dryer will have to work harder to exhaust air. Additionally, smaller diameters can increase the likelihood of lint accumulation in the duct, which poses risks such as fire hazards and mold growth due to insufficient airflow. Thus, the 4-inch minimum ensures a balance between adequate air movement and practical installation within residential structures, making it the correct choice for dryer exhaust duct standards.