What is the maximum number of clothes washers allowed on a three-inch stack?

The maximum number of clothes washers allowed on a three-inch stack is determined by plumbing codes that dictate drainage capacities and configurations. A three-inch stack has the capacity to accommodate multiple fixtures due to its larger diameter, which allows for better drainage and minimizes the risk of clogs and backups.

Specifically, installation codes often allow for multiple clothes washers to connect to a single sanitary stack, provided that the combined flow does not exceed the stack's capacity. The standard guideline permits a maximum of three clothes washers to be connected to a three-inch stack. This number considers the potential waste discharge from each washer and ensures that the plumbing system remains functional without creating issues in terms of drainage.

While other options present higher numbers, those exceed the recommended capacity for a three-inch stack, potentially leading to plumbing issues such as slow drainage or clogs. Thus, permitting three clothes washers strikes the right balance between efficient use of space in plumbing systems and maintaining operational integrity.