Domain surface · plumbing
Plumbing
Supply, drain, fixture, and water-heater work inside the building envelope. Main-line and lateral backups live on sewer so a faucet leak does not share a ticket shape with a collapsed lateral.
All trades · HVAC · Electrical · Sewer · Cross-trades
How this domain sits on the OS
Precipitation, freeze-thaw, and (only if they earn weight) experimental lunar/Earth-tide features may inform plumbing demand — they must not be assumed to cause residential leaks (§25.3). Water-heater swaps with vent, gas, or circuit work are cross-trades. Plumbing → HVAC turnovers are a first-class analytics slice (v0.7).
Common call types
Leak locate
Shutoff, finish protection, and photos before the wall closes.
Fixture stoppage
Trap/branch/vent — not automatically a sewer ticket.
Water heater
T&P, drain, combustion or circuit. Often a second trade.
Repipe / backflow
Estimate by zone. Test tags stay on the ledger.