Which component connects a Fixture Branch to the Waste Stack or Building Drain?

The correct answer is that the component connecting a Fixture Branch to the Waste Stack or Building Drain is the Horizontal Branch.

A Horizontal Branch is a plumbing component that serves as a horizontal pipe that collects and conveys wastewater from various fixtures within a building to the Waste Stack or Building Drain. Its main role is to ensure the effective removal of wastewater and maintain proper flow within the plumbing system. It typically connects multiple fixture drains and channels waste toward the vertical stacks, which then lead to the municipal sewer system or a septic system.

Understanding the function of the Horizontal Branch is critical for plumbing design and installation, as it directly influences the efficiency and functionality of the system. Knowing how this component integrates with both the Fixture Branch and the Waste Stack or Building Drain underscores its importance in maintaining a well-functioning drainage system in residential and commercial plumbing.