Plumbing Fixture Count Calculator

Required water closets, lavatories, drinking fountains, and service sinks by occupant load and occupancy — IBC 2902.1 / IPC Table 403.1.

Provisional · coming soon

The fixture-ratio tables are being verified before this calculator goes live. IPC 403.1 ratios pending verified load. You can enter your inputs below now; the computed counts will appear here once the verified ratios are loaded.

Required fixture counts will compute here once the verified IPC 403.1 ratios are loaded.

How this is calculated

Required plumbing fixtures come from the occupant load split by sex (default 50/50 per IPC 403.1), with the water-closet, lavatory, drinking-fountain, and service-sink ratios for the occupancy applied and each result rounded up to the next whole fixture. A service sink is a flat minimum of at least one. Always verify against local amendments — jurisdictions frequently amend Chapter 29. For the full method, see our plumbing fixtures guide.

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This calculator uses model code references for general reference. It is not a substitute for the adopted code and amendments enforced by your local authority having jurisdiction. Always verify against the edition and amendments your jurisdiction has adopted.

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