Home›Knowledge›UPC 422.1 — Minimum Plumbing Fixture Count
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UPC 422.1 — Minimum Plumbing Fixture Count

Updated May 22, 2026
Required number of water closets, lavatories, urinals, drinking fountains, and service sinks by occupancy and occupant load.

Implementation in src/lib/mep-load-calc.ts calculatePlumbingFixtures(). Note: real UPC 422.1 separates M/F counts; our calc uses a combined ratio for early scoping and flags the simplification.

TAGS
UPC422.1plumbing-fixturesoccupant-loadCPC-Table-4-1
DETAILS
book
UPC 2024
section
422.1
mep calc workflow
q-equipment-schedule
SOURCES
🔗https://codes.iccsafe.org/content/UPC2024P1
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