Code Applied by the app plumb.water.distribution-min
Minimum water service size
The water service pipe from the main to the building is never smaller than 3/4 inch; the pipes past it are sized to the fixtures they serve.
| When | The app uses |
|---|---|
| Water service pipe | 3/4 in |
- Source
- IPC · 603.1 · read the public text
- Editions checked
- 2018 · 2021
- Used by
- Bid Check
- Amendments
No state or local amendment to this rule is on file. Not on file means the model code as written — check your jurisdiction.
A model code the authority having jurisdiction adopts.
The service from the utility main to the building is sized for the whole load by the Appendix E method, but whatever that gives, it is never smaller than 3/4 inch. Inside the building the distribution piping has no single floor of its own: each fixture supply has its minimum (the fixture supply rule), and the branches and mains between are sized to the fixture units they carry.
What the app does with it
Bid Check's water rows (rung 6 of the water-sizing ladder) warn when a run that reads as the service (the first run in from the meter, or one named service) is smaller than 3/4 inch. Until then the value sits in the rulebook for the estimator to read.
What it does not do
It does not find the meter or the point of entry on the drawing; the estimator's line type names say which run is the service.
Verify against your edition
603.1 in the 2021 text, as a state adoption prints it, sets the water service at not less than 3/4 inch. A water purveyor or a jurisdiction may require more. Settled 2026-09-27 by Claude on the owner's delegation, from the dossier's research and the model code text; not checked against a printed book or a local amendment.
Cited by section, not reprinted: the code text belongs to its publisher. Company practice is not a rule here — it lives with your pricing.