ADU Plumbing in San Diego: Rough-In to Final Inspection
Water, sewer, and gas for new detached units, garage conversions, and junior ADUs. We work with your builder or your plans, handle the underground, the rough-in, and the finish, and pass the inspections in between.
- 24/7, no after-hours upcharge
- One-year labor warranty
- CA License C-36 #1157656
Sound familiar? It is worth a call.
- You have ADU plans approved or in review
- Your builder needs a licensed plumber for the underground and rough-in
- Converting a garage and need a bathroom and kitchen where there was none
- Your existing sewer lateral or water service may not have capacity
- The ADU needs its own water heater and shut-offs
Underground: trenching and tying new sewer and water lines into the existing lateral and service, sized for the added load, with the city connection inspection. Rough-in: supply and drain to every fixture location, vent stacks, and gas to the range and water heater, inspected before walls close. Finish: fixtures, water heater (tankless is the usual choice for the space), and final inspection. We can also assess whether your existing sewer lateral and water meter can carry the added unit, which is a question the city will ask and a builder often does not.
Send us the plans, or book a site visit if you are pre-plans.
Flat quote by phase: underground, rough-in, finish.
We schedule around the builder's framing and pour dates.
Each phase is inspected. Final is signed off with the rest of the unit.
What this county does to plumbing.
The county's ADU rules are among the most permissive in the state and the volume of detached units and garage conversions across San Diego, Vista, Oceanside, Escondido, and Chula Vista reflects it. The plumbing problems are consistent. Older lots have a four-inch clay or cast iron lateral that is already marginal, and a second kitchen and bath tips it. Water service is often three-quarter inch and the added fixture count may require an upgrade. Detached units usually get their own tankless water heater because there is no space for a tank and a long hot run from the main house wastes water. We flag capacity issues at the plans stage so they are in the budget, not discovered at inspection.
Flat, in writing, before we start.
Quoted flat per phase from the plans. Lateral or water service upgrades are quoted separately if the assessment shows they are needed. One-year labor warranty.
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Answered straight.
Do you work with my builder?
Yes. We are a sub on most ADU jobs and schedule to the builder's timeline.
Can my existing sewer line handle an ADU?
Sometimes. We camera it and check the size. If it is failing or undersized, replacing it before the ADU goes in is far cheaper than after.
Does the ADU need its own water heater?
Usually, for a detached unit. Garage conversions can sometimes share the main house heater if the run is short.
Tank or tankless for the ADU?
Tankless in most cases. It fits on a wall and does not eat floor space.
Do you handle the gas?
Yes, from the meter or manifold to the ADU appliances, with the capacity check.
How many inspections?
Typically three on the plumbing side: underground, rough-in, and final.
Get it handled.
Flat quote before any work starts, one-year labor warranty, and a licensed plumber on the truck.