What is the function of the main stack in a plumbing system?

The main stack plays a crucial role in a plumbing system by carrying waste and venting gases to the roof. This vertical pipe, typically extending through multiple floors of a building, facilitates the removal of sewage and wastewater from all plumbing fixtures. It ensures that waste is directed away from the building effectively and safely into the municipal sewer or a septic system.

Additionally, the main stack serves as a venting system, allowing harmful gases and odors to escape into the atmosphere instead of accumulating within the building. By connecting to vent pipes that open outside, the main stack helps maintain proper air pressure within the drainage system, preventing the potential for siphoning of water from traps, which could lead to sewer gas entering living spaces.

Importantly, this function is distinct from other options such as distributing clean water, filtering wastewater, or providing water pressure, as these involve different systems or components of plumbing that are not directly related to the main stack’s primary responsibilities.