Pipe Sizing

Water supply by fixture units; drainage by DFU.

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Formula and source

Water-supply size from Hunter's Curve fixture units (DFU per IPC 2021 Section 709, Table 709.1); WSFU for water supply per IPC Section 604, Table 604.3.

IPC 2021 (International Plumbing Code). Sections 604, 709, Tables 604.3 and 709.1. Hunter's Curve methodology by name.

Audience

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