Plumbers Insurance Requirements in Washington

Plumbing failures often do not become apparent until days, weeks, or even months after the work is completed. A slow leak from an improperly soldered joint can cause extensive mold growth and structural damage behind walls before it is detected. Completed operations coverage ensures the plumber's GL policy will respond to claims arising from their work after the project is finished.

Yes. Gas line work introduces explosion and carbon monoxide risks that significantly increase liability exposure. Most property managers require $2M per occurrence and $4M aggregate for plumbers performing gas piping installation or repair. Verify that the plumber holds a separate gas fitting license or certification as required by your jurisdiction.

Pollution liability covers claims arising from the release of contaminants, which is relevant for plumbers who work on sewer lines, septic systems, or waste piping. A sewer backup can introduce raw sewage into occupied spaces, creating a health hazard and costly cleanup. If your plumber performs any sewer or drain work, requiring $500K in pollution liability is a prudent risk management measure.

Even sole proprietors should carry general liability insurance. While workers' compensation requirements vary by state for sole proprietors, many jurisdictions treat uninsured subcontractors as employees of the hiring entity. This means if an uninsured plumber is injured on your property, your workers' compensation policy may be responsible. Require all plumbing contractors to carry WC regardless of employee count, or obtain a state-issued exemption certificate.

Verify that the GL policy is current, includes completed operations coverage, and meets your minimum limits ($1M/$2M minimum). Confirm the property owner is listed as additional insured. Check that workers' compensation is active with statutory limits. For gas work, verify the higher $2M/$4M GL limits and ensure the plumber's license covers gas fitting.

Washington L&I licenses plumbing contractors. Must hold a journeyman plumber certificate and contractor registration under RCW 18.27. Surety bond required.

In Washington, you as the property manager could be held liable for injuries or damages caused by an uninsured plumbers on your property. Washington courts have consistently ruled that property owners have a duty to verify contractor insurance before allowing work to begin.