Type L vents shall terminate not less than _________ above the highest point of the roof penetration.

Type L vents are specifically designed for the venting of appliances that produce flue gases, typically where the venting materials are subject to lower temperatures and less pressure. According to the North Carolina Mechanical Code, these vents need to be installed with specific considerations to ensure safe and effective operation.

The requirement for Type L vents to terminate a minimum of 2 feet above the highest point of the roof penetration is crucial for preventing backdrafts and ensuring that flue gases are safely exhausted away from the building structure. This height helps to maintain proper draft conditions for the vent, ensuring that any exhaust is carried well above the roofline, which avoids the risk of recirculating flue gases back into the building.

By adhering to this regulation, you help ensure the safety and efficiency of the appliance being vented, as well as comply with local codes and standards designed to protect both property and occupants.