What interior finish is required for exhaust ducts?

The requirement for exhaust ducts to have a smooth interior finish is crucial for several reasons related to efficiency and safety. A smooth interior finish minimizes friction and turbulence within the duct, which allows for more efficient airflow. This promotes better ventilation, ensuring that the exhaust is effectively removed from the space and preventing the buildup of moisture, odors, or potentially harmful gases.

Moreover, a smooth surface is easier to clean and less likely to accumulate dust, grease, and other debris that could obstruct airflow or pose a fire hazard. This attribute is especially important in systems like kitchen exhausts, where grease buildup can lead to significant safety issues if not managed properly.

In terms of compliance with codes, the use of smooth interior finishes is often stipulated in mechanical codes to promote optimal performance and safety in HVAC systems, particularly in regards to exhaust systems handling potentially combustible or irritant materials.