Lead flashing for 3-inch and 4-inch vent stacks shall have a minimum what size base?

The correct size for the base of lead flashing used for 3-inch and 4-inch vent stacks is 12 inches. This specification is crucial to ensure proper water drainage and prevent leaks. The 12-inch base allows for adequate coverage over the vent stack and surrounding roofing material, ensuring that water can easily flow away from the penetration point. This helps to minimize the chances of water pooling around the vent stack, which could lead to water intrusion and potentially cause damage to the roofing system or interior spaces. Additionally, the size contributes to the overall integrity of the roofing system by providing a robust barrier against environmental elements, acknowledging that various weather conditions can impact the performance of the flashing.