How should a horizontal stack offset be vented when there are more than four branch intervals below the top of the stack?

When dealing with a horizontal stack offset with more than four branch intervals below the top of the stack, venting must be conducted according to the International Plumbing Code (IPC) Section 907. This requirement is in place to ensure proper air circulation within the drainage system and to prevent the creation of negative pressure that can lead to trap seal loss in fixtures connected to the stack.

Section 907 outlines the necessary venting standards that must be adhered to in such situations, including the appropriate location and sizing of vents. This is essential for maintaining the functionality and safety of the plumbing system. By following these guidelines, plumbers can ensure that waste can escape effectively without causing any obstruction or backpressure, maintaining the integrity and performance of the drainage system.

In this context, omitting venting, venting only if oversized, or stating that no venting is required would not comply with the standards necessary for safe and effective plumbing operation. Therefore, understanding and applying the requirements set forth in IPC Section 907 is crucial for any plumbing installation involving a horizontal stack with multiple branch intervals.