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Drainage Pipe Slope Calculator vs Plumbing Fixture Unit Calculator

Two calculators for the same neighbourhood of questions. Here is what each measures, what you feed in, and where you'd reach for one over the other.

Plumbing

Drainage Pipe Slope Calculator

Calculates the required slope and total vertical fall of a drainage pipe to achieve self-cleaning sewage flow over a given horizontal distance. Essential for plumbers designing gravity-fed drain systems.

Answers
Required Fall (inches)
Inputs
Pipe Diameter, Horizontal Distance, Expected Flow Rate
Plumbing

Plumbing Fixture Unit Calculator

Add up the drainage fixture units (DFU) for every toilet, sink, shower, bathtub, and appliance in a building to find the correct supply and drain pipe sizes per plumbing code. Essential for new construction, additions, or remodels.

Answers
Total Fixture Units (FU)
Inputs
Number of Toilets, Number of Sinks, Number of Showers, Number of Bathtubs, Other Appliances

At a glance

Drainage Pipe Slope CalculatorPlumbing Fixture Unit Calculator
CategoryPlumbingPlumbing
AnswersRequired FallTotal Fixture Units
Inputs35
Result unitinchesFU

When to use each

Calculates the required slope and total vertical fall of a drainage pipe to achieve self-cleaning sewage flow over a given horizontal distance. Essential for plumbers designing gravity-fed drain systems.

Add up the drainage fixture units (DFU) for every toilet, sink, shower, bathtub, and appliance in a building to find the correct supply and drain pipe sizes per plumbing code. Essential for new construction, additions, or remodels.

Compare page seeded from editorial siblings — both calculators list each other as related.