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Plumbing

Fixture Unit Demand Calculator

Computes the total plumbing demand load in fixture units for toilets, sinks, showers, and appliances, then converts it to a peak flow estimate for pipe sizing. Use it when designing or auditing a building's water supply system.

Fill in the required fields to see your result.
Plumbing

Plumbing Fixture Unit Calculator

Calculates total plumbing fixture units (FU) for a building by summing standardized load values for toilets, sinks, showers, and tubs. Use it to size drain, waste, and vent (DWV) or water supply piping per code.

Fill in the required fields to see your result.

Key differences

Fixture Unit Demand CalculatorPlumbing Fixture Unit Calculator
CategoryPlumbingPlumbing
Inputs required54
ResultPeak Demand (GPM)Total Fixture Units (FU)
What it doesComputes the total plumbing demand load in fixture units for toilets, sinks, showers, and appliances, then converts it to a peak flow estimate for pipe sizing. Use it when designing or auditing a building's water supply system.Calculates total plumbing fixture units (FU) for a building by summing standardized load values for toilets, sinks, showers, and tubs. Use it to size drain, waste, and vent (DWV) or water supply piping per code.