Plumbing Calculator

Calculate pipe sizing, water flow, fixture units, and drainage requirements

Plumbing System Analysis

Calculation Type

Enter plumbing specifications to calculate requirements

Toilet: 4 fixture units
Standard residential toilet

Sink: 1 fixture unit
Bathroom or kitchen sink

Shower: 2 fixture units
Standard shower stall

1/2 inch: 8 GPM maximum
Branch lines to fixtures

3/4 inch: 13 GPM maximum
Main supply lines

1 inch: 21 GPM maximum
Service entrance

Minimum Slope: 2% (1/4" per foot)
For proper drainage

Vent Requirements: Every fixture
Prevents siphonage

Cleanouts: Every 100 feet
For maintenance access