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Fixture Unit Calculator

IPC Table 604.1 · WSFU + DFU · Water Supply & Drain Sizing

When to use: Count plumbing fixtures to determine total water supply fixture units (WSFU) and drainage fixture units (DFU) per IPC Tables 604.1 and 709.1. WSFU drives water supply pipe sizing; DFU drives drain, waste, and vent (DWV) sizing. Required first step for all IPC plumbing system designs before pipe sizing.

Fixture Count

Water Closet – flush tank2.5W/4D

Water Closet – flush valve6W/4D

Urinal – flush valve5W/4D

Lavatory (faucet)1W/1D

Kitchen Sink1.5W/2D

Service Sink3W/3D

Bathtub / Shower (combo)1.5W/2D

Shower Stall1.5W/2D

Dishwasher1.5W/2D

Clothes Washer2W/3D

Drinking Fountain0.5W/1D

Floor Drain (2")0W/2D

Total WSFU

0.0

Water Supply Fixture Units

Summary

Total Fixtures0

Total WSFU (water supply)0.0

Total DFU (drainage)0.0

References

IPC Table 604.1 – WSFU per fixture

IPC Table 709.1 – DFU per fixture

IPC Section 604 – Water supply sizing

Use WSFU total → Pipe Sizing Calculator