What component connects the building drain to the municipal sewer system?

The component that connects the building drain to the municipal sewer system is known as the building sewer. This section of plumbing is crucial as it serves as the conduit through which wastewater is transported from the building's drainage system to the larger municipal sewer lines.

The building sewer begins at the building's foundation wall and usually extends to the point of connection with the municipal sewer system or to a septic system where applicable. The design and installation of the building sewer must comply with local plumbing codes to ensure proper flow and to prevent backflow, which could contaminate the building's drainage system.

While building drain, building vent, and building trap play important roles in the plumbing system, they serve different purposes. The building drain refers to the system within the building that collects wastewater from fixtures. The building vent provides air circulation to maintain proper pressure within the drainage system, aiding in the efficient movement of wastewater. The building trap, on the other hand, is a component that prevents sewer gases from entering the building while allowing wastewater to flow through.

Understanding the specific roles of these components is essential for proper plumbing design and compliance with the plumbing code. The building sewer's primary function as the connector between the building and the municipal sewer system underscores its importance in the overall plumbing infrastructure.