What counts as tenant improvement plumbing?
TI plumbing is any work needed to make a leased space fit its next use: adding or relocating restrooms to meet occupant load, running a floor drain and grease interceptor for a food tenant, plumbing a break room or mop sink, capping and rerouting lines left by the last tenant, or tying new fixtures into an existing stack that was never sized for them. It's distinct from residential remodel plumbing mainly in the paperwork — occupancy classification, accessibility counts, and often a separate mechanical or health department sign-off if food or water service is involved. See our broader commercial plumbing service & repair for ongoing maintenance once the space is open.
When do you need it?
Most calls come from a GC or tenant mid-buildout: a shell space with stub-outs in the wrong place, a change-of-use permit that triggers a new fixture count, or a landlord who wants plumbing priced before signing a lease. Older Portland buildings — brick storefronts on Division or Alberta, converted warehouses in the Central Eastside, strip retail out in Beaverton and Hillsboro — often have cast iron or galvanized branch lines that won't support a new restroint group or grease trap without upsizing first. Finding that out before the schedule is set saves a change order later.
How the visit goes
For a quote, we walk the space with the plans or, if there are none yet, sketch what's there and what's needed against the fixture count the permit will require. We check the water and sewer service size at the meter and the point of connection, look at venting, and flag anything — old cast iron, undersized branch lines, no cleanout access — that changes scope. For the work itself: rough-in happens after demo and before insulation/drywall, we schedule around the other trades (electrical and HVAC usually run the same walls and ceiling space), and trim-out — fixtures, faucets, water heater or point-of-use unit — goes in near the end, timed to the inspector and the punch list. A licensed plumber pulls the permit and is on-site for rough and final inspections.
What affects the price
Distance from the existing stub-outs to the new fixture locations, whether the branch or main lines need upsizing, floor drains and interceptors (concrete cutting adds cost), the number of fixtures and whether ADA-compliant units are required, and how tight the schedule is against other trades. A space with plumbing already roughly where you need it costs a lot less than one where every line moves. We quote off the plans, not a guess.
What's specific to Portland plumbing and buildings
Portland's older commercial stock — much of it pre-1960 brick and wood-frame — was plumbed for a single tenant, not the fixture counts modern change-of-use permits require, so a lot of TI work is really "make this 1920s branch line do 2020s work." The city and most metro jurisdictions (Multnomah, Washington, Clackamas counties) require separate plumbing permits and inspections from the building permit, and inspectors want cleanouts accessible, not buried behind finished walls — worth planning for before drywall goes up. Wet winters mean any new floor drain or exterior connection gets checked for backflow protection; it's cheaper to build it in than retrofit after a failed inspection.
Why Sheltons Construction
We're a licensed Oregon plumbing contractor working the Portland metro day in, day out on both residential and light-commercial jobs. We pull our own permits, show up for rough and final inspections, and quote off what's actually in the walls, not a rough guess. If a job also needs new construction plumbing, water heater or tankless water heater sizing, water pressure checks, or a sewer camera inspection before you commit to a lease, we handle that under the same visit.
What to do now
If you have plans and a schedule, send them through contact and we'll quote the rough-in and trim-out against your permit timeline. If you're still evaluating a space, we can walk it first and tell you what the existing plumbing will and won't support before you sign anything. Talk to your GC about timing — TI plumbing works best coordinated trade to trade, not scheduled in isolation.
Where we work
Serving Portland, Beaverton, Hillsboro, Gresham, Tigard, Tualatin, Lake Oswego, West Linn, Oregon City, Milwaukie, Happy Valley, Clackamas, Wilsonville, Troutdale, Sherwood, and down to Salem for larger or scheduled work. See the Portland area page for details, or check our FAQ for common questions on permits and scheduling.