Short definition
Permits and inspections are the two halves of the local building authority’s enforcement process. A permit grants written authorization to do specific work; an inspection verifies the executed work meets code. Most WA plumbing permits run through three inspection stages — underground, rough-in, and finish — and the permit closes only when the final inspection passes.
What it is
The process, end to end:
- Application. Contractor or homeowner submits a scope of work and supporting drawings. Some jurisdictions require plan review for complex projects (additions, basement bathrooms, repipes); simple permits issue same-day.
- Permit issuance. Fees paid; permit number assigned. Work can begin.
- Underground inspection. Sub-slab drain layout, slope, materials, joints, and pressure test verified before backfill or concrete pour.
- Rough-in inspection. In-wall pipework, supports, nail plates, fire blocks, and pressure test verified before drywall.
- Finish (final) inspection. Fixtures connected, water-heater straps, drain operation, pressure-test under operating conditions, all visible elements verified.
- Permit closure. Final inspection passes; the permit closes; the work is on the property record.
Each inspection is a separate event, scheduled by the contractor (or homeowner on owner-pulled permits) within the permit window. A failed inspection generates a correction list; the contractor fixes the items and re-schedules.
The permit itself has an expiration window — typically 18 months in Seattle SDCI from issuance with no inspection activity. Letting a permit expire without closing creates a title defect; reopening or extending requires AHJ action.
Why it matters to a homeowner
The permits-and-inspections process is the cheapest, most reliable second opinion you’ll ever get on plumbing work. The permit fee buys you a state-licensed inspector verifying that your contractor did the work to code. That’s an enormous protection at a small price.
Three things every homeowner should know.
Drywall waits for rough-in inspection. This is the most common code violation on residential remodels: contractors hang drywall to keep the project moving, then the inspector arrives and orders it removed. The inspector has the authority. Don’t waive it.
Open permits at sale are problems. When you sell, the title company runs a permit search. Open permits — issued but never closed — are flagged for the lender or buyer. Resolution can mean re-inspection (often easy) or estoppel inspection (more involved if the original work is gone or noncompliant). Close every permit on every project before you sell.
Insurance leverage. A water-damage or sewer-line claim from a leak in unpermitted work can be denied. Permits and their closing inspections are documentation that the work was done legally. Keep your permit closure paperwork with your home records.
When a contractor’s quote is missing the permit fee or the inspection scheduling is unclear, ask. A reputable WA contractor includes both.
When you’ll encounter this term
- Any non-trivial plumbing project.
- A title search at sale flagging an open permit.
- A bathroom remodel scheduling discussion.
- An insurance claim adjuster requesting permit numbers.
Common variants and disambiguation
- Permits vs. inspections. Permits authorize; inspections verify. Different fees, different schedulers, both required.
- Underground vs. rough-in vs. final. Three distinct inspection points, each must pass before the next phase proceeds.
- Permitted work vs. grandfathered. Permitted work is documented; grandfathered work is legal nonconforming legacy that doesn’t have to be permitted unless re-opened.
Washington note
In WA, every permit-required plumbing project ends with a final inspection by the AHJ; an open permit is a title defect, and lenders flag them at sale. The legal framework: WAC 51-56 (WA-amended UPC) is the plumbing code; WAC 51-52 is mechanical (gas appliances, hydronic heating); WAC 51-11C/R is energy (WSEC). Inspectors enforce all three at the relevant inspection stages.
Seattle SDCI handles plumbing permit intake and inspection scheduling at https://www.seattle.gov/sdci. Standard permit window is 18 months from issuance with no inspection activity. Side sewer permits moved to Seattle Public Utilities (SPU) on October 1, 2025; everything from the building foundation to the public sewer main is now SPU’s jurisdiction in Seattle.
King County DLS, Tacoma Permits, City of Bellevue Development Services, and other WA jurisdictions handle their own permits and inspections under WAC 51-56 enforcement. Permit fees and procedures vary; verify locally.
For homeowners doing their own work on owner-occupied single-family residences in WA, most jurisdictions allow homeowner-pulled permits — the homeowner becomes the responsible party for the work and must schedule and pass inspections. Side sewer work in Seattle is the major exception: a SPU-registered side-sewer contractor must pull and execute the permit; homeowners cannot self-permit.