ADU Plumbing Rough-In & Installation

Your ADU project starts with the plumbing — get it done right from the ground up and avoid costly corrections later.

Adding an accessory dwelling unit to your property is a significant investment. The framing, the finish work, the electrical — all of it depends on the plumbing being done correctly first. A rough-in that is off by even a few inches creates problems that ripple through every phase that follows. At Smith Plumbing, ADU plumbing has been a core part of our work for years. James Smith brought commercial plumbing standards to this work from day one, and the result is rough-ins that pass inspection the first time and installations that hold up long after the project is complete.

We handle the full plumbing scope on ADU projects — from initial rough-in through final fixture installation. That includes running new supply and drain lines from the main home connection, setting the rough-in for bathrooms and kitchens, coordinating with your general contractor on timing, and completing the final trim-out when the walls are closed and the finishes are in. We know what inspectors in the High Desert look for, and we build to that standard from the start rather than correcting issues at the inspection stage. Homeowners in Hesperia, Oak Hills, Victorville, and the surrounding communities have relied on us to get their ADU plumbing done right without holding up the rest of the build.

If you are planning an ADU in Hesperia or anywhere in the High Desert, call Smith Plumbing early in the process at (760) 220-8120. Getting the plumbing scoped and scheduled before framing begins saves time and prevents the kind of coordination problems that slow builds down. We are a family-owned business with no commission driving our recommendations — just straightforward work done to a high standard.

What We Offer:

ADU Plumbing Rough-In – We set all rough-in plumbing to the correct specifications before walls are closed — supply lines, drain lines, vent stacks, and fixture placements — so every phase that follows lines up correctly.
Supply & Drain Line Extension – We run new supply and drain lines from your main home connection to the ADU, sized and routed properly to support the full plumbing load of the new unit.
Bathroom Rough-In & Trim-Out – From setting the shower pan drain and toilet flange to installing final fixtures after the walls are finished, we handle the complete bathroom plumbing scope in your ADU.
Kitchen & Laundry Plumbing – We rough in and install kitchen sink connections, dishwasher lines, and laundry hookups — everything needed to make the ADU fully functional as a living space.
Water Heater Installation for ADU – We install a dedicated water heater for the ADU — tank or tankless depending on the space and your preference — and connect it properly to the new unit's supply system.
Inspection-Ready Work – Every phase of our ADU plumbing is done to code and built to pass inspection without corrections. We know what local inspectors require and build to that standard from the rough-in stage forward.
General Contractor Coordination – We work directly with your GC to make sure plumbing phases are completed on schedule and do not hold up framing, drywall, or finish work.

Why Choose Smith Plumbing for ADU Plumbing Rough-In & Installation

Years of ADU Plumbing Experience – ADU work has been part of Smith Plumbing's core services since James shifted to residential work. We have completed ADU plumbing scopes across the High Desert and know the process from start to finish.
Commercial Standards Applied to Residential Work – James's background in commercial plumbing through the union means every rough-in is precise, every connection is solid, and the work is built to a higher standard than most residential projects require.
Passes Inspection the First Time – We know what inspectors look for in Hesperia and the surrounding High Desert communities. Building to that standard from the beginning means no costly corrections, no delays, and no second inspection visits.
Full-Scope Coverage – We handle the complete plumbing scope on ADU projects — rough-in through final trim-out. You do not need a separate plumber for each phase or worry about handoff issues between contractors.
No Commission, Honest Scoping – When we assess an ADU plumbing scope, the estimate you receive reflects what the job actually requires. There is no incentive to pad the scope or recommend work that is not necessary.