What the demo gives you.
Total WSFU and DFU, plus a service-size class — enough to sanity-check a service or a whole-home count.
Free demo · Fixture units
Fixture unit calculator.
Count the fixtures, get the units — water supply (WSFU) and drainage (DFU) totals with a service-size class, from published code tables. The demo stops at the headline number; inside NectARM the same math sizes branches and feeds the drawing.
Total fixture units
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Enter counts and calculate. Results use published UPC/IPC-style tables — the same public math the product's calculator starts from.
What stays inside.
Branch-by-branch sizing, drawing-fed fixture counts, velocity checks, and the takeoff that comes off the result. That's the calculator stack — it feeds the CAD, not a web page.
Why it's still useful.
Fixture units are the currency of plumbing sizing. Knowing the total tells you the class of service a house needs before anyone draws a line.
The full version
This math feeds the drawing inside NectARM.
Fixture counts flow into sizing, sizing flows onto the runs, and the takeoff counts the result — one system, no re-typing the math.