Can I Run Bathtub, Kitchen Sink, and Vanity on One Drain?
When running plumbing in a back-to-back bathroom and kitchen setup, it’s essential to understand how to route the drainage properly. Here’s a breakdown of whether you can run your bathtub, kitchen sink, and vanity on a single drain line and how to manage the venting.
Q: Can I run a bathtub, kitchen sink, and vanity on the same 2″ PVC drain line, provided each fixture has its own dry vent?
A: Yes, you can run all three fixtures on a single 2″ drain line, as long as each fixture has its own dry vent.
Here’s how to make sure your plumbing setup works:
1. Drain Line Configuration:
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You can use a 2″ PVC drain line to connect the bathtub, kitchen sink, and vanity as long as you follow proper drainage guidelines.
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Each fixture, like the bathtub, kitchen sink, and vanity, should connect to the main drain line individually. This helps maintain proper flow and reduces the risk of clogs or backflow.
2. Dry Vents for Each Fixture:
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Each fixture must have its own dry vent to ensure that air can flow freely and prevent pressure from building up in the drain line.
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The dry vent for each fixture can connect to the main 2″ vent line down line. This is essential for allowing the system to function without blockages or slow drainage.
3. Using 1 1/2″ Vents:
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You can use 1 1/2″ vents for each fixture, but keep in mind that the venting size should be compatible with the drainage system.
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The 1 1/2″ vent will connect to a larger 2″ vent line later in the system. This is fine as long as the total venting capacity is enough to handle the airflow for all the fixtures.
4. Considerations:
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Ensure that each fixture’s vent line is properly sloped and connected to prevent blockages and ensure smooth airflow.
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Double-check local plumbing codes for any specific requirements for vent sizing or drain line configurations.
Conclusion:
Running a bathtub, kitchen sink, and vanity on the same 2″ drain line is possible if each fixture has its own dry vent. Using 1 1/2″ vents is acceptable, as long as the system is properly sized and connected. If you’re unsure, it’s a good idea to consult a professional plumber to ensure everything is up to code.
For more plumbing tips and advice, visit Plumbing 101.
I’m Chris Mayer, writing for Plumbing 101.
