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🔍 Drain Pipe Sizing Calculator

Determine correct drain pipe size based on fixtures served

🔢 Fixtures

📐 Recommended Drain Size

Minimum Pipe Diameter

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inches
Enter fixtures and calculate

📚 Drainage Fixture Units (DFU)

Each plumbing fixture is assigned a DFU value representing its load on the drainage system. The total DFU determines minimum pipe size according to plumbing codes.

General Rules:

  • 1.5" - Up to 3 DFU
  • 2" - Up to 6 DFU
  • 3" - Up to 12 DFU
  • 4" - Up to 32 DFU