OVERVIEWADU Plumbing in Sherwood, OR
Sherwood Plumbing handles ADU plumbing — rough-in, water service, and finish — for detached, attached, and basement-conversion units across Sherwood, Tualatin, and Tigard. Adding an accessory dwelling unit is one of the few ways left to add real space and rental income to a Washington County property — but the plumbing is where a lot of ADU projects stall. A detached unit needs its own drain, waste, and vent runs tied back to the main, a water supply that may need a new service line or sub-meter, and a finish stage that has to pass inspection before anyone moves in. We handle the plumbing side of ADUs start to finish, working alongside your general contractor or directly with you as the homeowner.
NEED A PLUMBER NOW?Call or text (503) 822-5070
WHAT YOU NEED TO KNOWWhat ADU plumbing services does Sherwood Plumbing provide?
We handle ADU rough-in, water service and hookups, and finish plumbing for detached, attached, and basement-conversion units.
ADU rough-in
We run the drain-waste-vent and supply lines for the new unit — kitchenette, bathroom, laundry, and water heater — coordinated with your framing and the rest of the trades so nothing gets buried that shouldn’t be.
Water service & hookups
Detached ADUs often need a new water service line off the main, and sometimes a separate sub-meter if you’re renting the unit out. We size and run the service, set the shutoffs, and tie in the water heater (tankless or tank).
Finish plumbing
Once the walls are closed, we set fixtures — sink, toilet, shower or tub, kitchenette, washer hookups — test everything under pressure, and get it ready for final inspection.
Detached, attached & basement conversions
Whether it’s a new detached unit in the back, a garage or basement conversion, or an attached addition, the plumbing approach changes. We’ve done all three across the south-metro.
GOOD TO KNOWWhat ADU plumbing scenarios does Sherwood Plumbing handle most often?
We most often work new detached ADUs, basement or garage conversions, and attached additions — each with its own plumbing approach.
New detached ADU. Backyard unit on its own slab — new DWV, a fresh water service run from the main, water heater, and a full fixture set. The biggest variable is how far the unit sits from the existing main.
Basement or garage conversion. The structure exists; the plumbing usually doesn’t. Below-grade bathrooms sometimes need an ejector pump because the drain sits below the sewer line — we’ll tell you up front if that’s the case.
Attached addition. Easier tie-in to the existing system, but it still has to be sized so the new fixtures don’t starve the main house.
OUR PROCESSHow does an ADU plumbing visit work?
Call or text to tell us your ADU project’s stage, and we’ll assess the site, give you a written scope and price, then handle rough-in through final inspection.
Call or text (503) 822-5070 and tell us where the ADU project is — planning, framed and waiting on rough-in, or ready for finish. If you have a GC, we’ll coordinate directly with them.
On site, we look at the plans, the distance to the main, and the existing service capacity, then give you a written scope and price before any work starts. ADU jobs run on a milestone schedule — a deposit to start, then payments tied to rough-in, inspection, and finish — so you always know what’s billed and why.
We pull the permits our scope requires and stay on through inspection so the unit clears the plumbing sign-off cleanly.
WORTH KNOWINGWhy Sherwood for ADU plumbing
Devin has been a working plumber for close to 20 years, and additions are exactly the kind of work the shop is known for — running new systems into spaces that never had them, sizing services correctly, and handling the inspection back-and-forth so the project doesn’t stall. We’re the only plumber actually headquartered in Sherwood, licensed through the Oregon CCB, carrying $1M general liability and a $25,000 surety bond.
ABOUT SHERWOOD PLUMBINGAbout the shop
Sherwood Plumbing has been running since 2013 under Devin Drew Adams. We’re headquartered in Sherwood, the only plumbing company actually based in town. Our techs know the housing stock around here: the 1970s gas tank in a Sherwood ranch, the 2015 tankless in a Villebois build, the electric tank in a Cedar Hills postwar home. That local knowledge is the difference between a diagnosis that takes 20 minutes and one that takes two hours.
We carry $1,000,000 in general liability through Contractors Bonding & Insurance. Oregon CCB license #200851 (Plumbing, Residential RGC General Contractor). PB1381 with the Oregon Building Codes Division. $25,000 surety bond. 220 Google reviews at 4.7 stars.
FREQUENTLY ASKED QUESTIONSFrequently asked questions
Yes. On most ADU builds we coordinate with the GC on scheduling and rough-in timing. We can also work directly with you if you’re acting as your own contractor.
Not always — it depends on your jurisdiction and whether you’re renting the unit. We’ll tell you whether a separate service line or sub-meter makes sense for your situation when we see the site.
Usually yes. If the bathroom sits below the sewer line, it needs an ejector pump to lift waste up to the main. We’ll confirm whether that applies before we scope the job.
We pull the plumbing permits our scope requires and stay on through inspection so the unit passes its plumbing sign-off.
It runs in stages — rough-in during framing, then finish once walls are closed — so the plumbing timeline follows the overall build. We schedule each stage with your contractor.
No — ADU plumbing depends too much on the site, distance to the main, and the plans. We come out, look at the actual conditions, and hand you a written price before any work begins.