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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.

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Plumbing

Water Pressure Loss Calculator

Calculates friction-induced pressure drop along a water pipe using the Hazen-Williams equation. Use it when designing irrigation systems, fire suppression lines, or building water supply networks where adequate pressure at the endpoint matters.

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Key differences

Fixture Unit Demand CalculatorWater Pressure Loss Calculator
CategoryPlumbingPlumbing
Inputs required53
ResultPeak Demand (GPM)Pressure Loss (PSI)
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 friction-induced pressure drop along a water pipe using the Hazen-Williams equation. Use it when designing irrigation systems, fire suppression lines, or building water supply networks where adequate pressure at the endpoint matters.