Offline
No internet, no account required.
IPC App.E
Validated against the standard.
PDF export
Pro-only. Generate professional reports.
$2.99 Pro
Lifetime unlock. No subscriptions.
How it works
Enter your values
Type in your inputs — the app fills code tables and constants for you, so there's nothing to look up.
Get a code-checked result
Instant answer with a clear PASS / FAIL and the exact IPC App.E reference behind every number.
Save & export
Keep a history of calculations and export a clean PDF report to share or attach to a permit (Pro).
What this calculator does
Commercial buildings have heavier and more varied water demand than homes. This app totals commercial water supply fixture units and converts them to peak demand so you can size the service and mains for offices, restaurants, schools, and other occupancies under the IPC.
How it works
- Enter the count of each commercial fixture; the app assigns its WSFU from the IPC commercial values.
- It applies Hunter's curve to get the probable peak demand in GPM.
- It separates flush-valve loads, which dominate commercial demand, from flush-tank fixtures.
Worked example
An office floor with flush-valve water closets, urinals, and lavatories can total well over 100 WSFU, translating to tens of GPM of peak demand — far more than a house and requiring a larger service.
Related calculators
Size the pipe with the water pipe sizing calculator and total units with the fixture unit calculator.
Commercial load FAQ
Why are commercial loads sized differently?
Commercial fixtures, especially flush valves, draw more and tend to be used in heavier bursts, so the fixture-unit values and the demand curve differ from residential work.
Does flush-valve versus flush-tank matter?
Significantly. Flush-valve fixtures carry much higher supply fixture units, so the app tracks them separately when totaling demand.
What occupancies does it suit?
Offices, restaurants, schools, retail, and similar buildings — anywhere you total commercial fixtures to size the service and distribution mains.
Does it work offline?
Yes, it runs 100% offline with no account. Free with rewarded ads; a one-time $2.99 Pro unlock adds PDF export and saved history.
Get Commercial Load on your phone
Free with rewarded ads · $2.99 lifetime Pro · iOS & Android. Works 100% offline on the job site.