Hiring a contractor for a roof, tree removal, side sewer, electrical or HVAC job in Washington
Which registration or licence to look for on each common job, what to ask, and how the trade categories on this site map to L&I's specialties.
The right credentials differ by job. This guide explains how the specialties in L&I's records map to the jobs homeowners hire for, and what to ask each kind of contractor. Always confirm on the L&I verification tool.
Roofing
Roofers register as construction contractors with the roofing specialty, and a general contractor can also manage a roof job. Ask what will be done about rotted decking, whether old layers are stripped, how the roof is ventilated and flashed, who pulls any permit your city requires, and how debris and moss treatments are handled during the wet season. Get the manufacturer and installer warranty in writing and ask what voids it.
Tree removal and tree service
Washington lists a tree removal service specialty for registered construction contractors. Cutting trees close to your house or power lines is dangerous work, and a bond and insurance are your protection if a limb hits your roof. Ask whether the price includes stump grinding and hauling, whether the company carries insurance you can see on the L&I page, and whether your city or county requires a permit for removing trees of a certain size or in a critical area. Rules vary by jurisdiction, so call your planning department first.
Excavation and side sewer
Excavation, grading and land clearing and side sewer contractors register with L&I like other specialty contractors. A side sewer is the pipe that carries wastewater from your house to the public sewer, so the work normally involves the city or sewer district, permits and inspections. Ask the contractor who applies for the permit, who arranges the inspection and whether the price includes restoring driveways, sidewalks and landscaping. Get a written scope for what happens if the pipe route hits rock, other utilities or groundwater.
Electrical
An electrician needs an electrical contractor licence with a $4,000 bond. Electrical work generally requires an electrical permit and an inspection; in most of Washington the permit comes from L&I, though some cities run their own program. Ask for the permit number and confirm that an inspection is scheduled. The electricians listed here show a bond, and you should ask separately for a liability certificate.
Plumbing
Plumbing contractors are licensed by L&I, and the plumbers doing the work hold a certificate of competency. Ask whether your job needs a permit, who pulls it and whether the plumbers on the crew are certified.
HVAC
Heating and cooling work involves several credentials: a construction contractor registration with the HVAC/refrigeration specialty, and for electrical wiring an electrical licence. Ask which licence covers which part of the job, whether the equipment is sized by a load calculation, and what the warranty covers for parts and labour.
General contractors and remodelers
For larger remodels and additions a general contractor coordinates the trades. Ask who the subcontractors are, whether they are registered, and who is responsible when they are not paid. See our guide on bonds, insurance and liens.
Questions to ask any contractor
- What is your L&I registration or licence number, and may I check it now?
- Who is your bonding company and insurer?
- Do you subcontract any of the work?
- What permits are needed, and who is responsible for them?
- Can I have three references from jobs like mine in the last year?
- What is your payment schedule?