Fixture Units Calculator
Calculate total drainage fixture units (DFU) and minimum drain pipe diameter based on plumbing fixture counts.
How to Use the Fixture Units Calculator
- Enter the count of each fixture type.
- Click Calculate for total DFU and minimum pipe diameter.
Anwendungsfälle
- •Drain pipe sizing for new construction.
- •Plumbing renovation planning.
- •Building permit applications.
- •Plumbing engineering education.
Formel
DFU: toilet=4, sink=1, shower=2, bathtub=3, dishwasher=2, washing machine=3. Pipe size from IPC table.
Häufig gestellte Fragen
What is a fixture unit?
A drainage fixture unit (DFU) is a measure of probable wastewater flow. 1 DFU ≈ 28 L/min.
What pipe sizes do different DFU totals require?
0–3 DFU: 50mm. 4–10: 75mm. 11–30: 100mm. 31–60: 125mm. >60: 150mm.
Are these values for horizontal or vertical pipes?
These are for horizontal branch drains. Vertical stacks and building drains may differ.