General information
Washington State requires all construction contractors to register with the State Department of Labor & Industries (L&I). RCW Section 18.27.040 also requires construction contractors to be bonded and insured to protect the public.
If you are unable to resolve serious problems with a contractor, you can file suit against their bond. The Washington State Department of Labor & Industries has general information and a more detailed publication about filing a lawsuit against a contractor's bond.
Self-help kit from the law library
The law library sells a Start a Contractor's Bond Claim self-help kit with forms and instructions to start a claim against the contractor's bond (it does not cover how to finalize the process). It includes forms for either the homeowner or a subcontractor/supplier who has not been paid. Kits can be purchased at the library or online and mailed out.