Permit Required
Do you need a permit to install a gas line in Seattle, WA?
Gas piping is not covered by a mechanical permit; installing or extending a gas line requires its own separate permit (the mechanical permit explicitly excludes gas lines, plumbing, and boilers).
✓ Verified from official source
Source: Seattle SDCI — Mechanical Permit — Verified 2026-06-26
Permit rules vary by property and change over time. This is an informational guide, not legal advice — always confirm with Seattle Department of Construction and Inspections (SDCI) before starting work.
How to get the permit in Seattle
Building department
Apply online
Phone
(206) 684-8600
Code in force
2021 Seattle Residential Code (Seattle's amended adoption of the 2021 IRC)
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