Insurance for Metal Fabricators and Welders
A welder’s worst day usually starts with a spark, whether at a client’s warehouse, on a farm or in your own shop beside a rack of finished railings. We look for welding insurance and metal fabrication insurance that follows the work from the shop floor to the jobsite, and the insurer decides after reviewing what you build, where you weld and who is on the crew.
Shop fabricator or mobile welder: two kinds of welding insurance file
Insurers split this trade in two. A shop fabricator builds and sells products such as ornamental gates, railings, stairs, plate steel tanks and structural members, so product liability and the buyers who demand certificates drive the file. A mobile welder brings the rig to the work: repairing a truck frame, a farm implement or a client’s equipment, or welding on a building under a general contractor. That file turns on jobsite liability, the truck and the gear on it.
Plenty of businesses do both, and the application should show how revenue divides between shop sales, repair calls and construction work, because each part is rated and classed differently. Precision parts work that never leaves the building is closer to our page on insurance for machine shops, and plant-wide questions sit on insurance for manufacturers.
Hot work at a client’s site: fire watch and general liability
Sparks and slag travel. When welding at a client’s site sets fire to the building or the goods stored in it, the claim lands on your general liability as damage to someone else’s property. Ask whether a quoted policy carries any hot-work or fire-watch condition before you bind it, and tell us if a contract calls for a hot-work permit system on site.
Cal/OSHA’s Title 8 section 4848 requires employers to set up a fire prevention and suppression procedure based on ANSI Z49.1 and chapters 3 to 7 of NFPA 51B-2009, and it requires welding blankets and curtains to be approved. The familiar field rules come from NFPA 51B: a fire watch whenever combustibles sit within 35 feet of the work, kept for at least 30 minutes after welding stops. A written procedure and a signed fire-watch log are what an underwriter and a claims adjuster both ask to see.
Railings, stairs and trailer hitches after delivery
A welded hitch that separates on the highway, a balcony railing that gives way, a bracket that cracks under load: these are products-completed operations claims. Under California’s strict liability rule from Greenman v. Yuba Power Products (1963), the injured person does not have to prove you were careless, only that the item was defective when it left your hands.
Steel that is installed in a building stays with you a long time. A hidden defect in installed steel can be sued on for up to ten years after substantial completion under Code of Civil Procedure 337.15, and willful misconduct or fraudulent concealment removes even that cutoff. Keep completed-operations coverage in force and keep weld records and inspection sign-offs for the whole period. Insureon also lists professional liability for welders, for claims that a welded item failed because of a design or specification error.
The welding rig: commercial auto, welders and gas cylinders
A mobile welding truck is a working vehicle with a generator, leads, torches and cylinders mounted on it. List every rig and every driver on commercial auto, and tell us what is bolted to each truck, because the vehicle and the equipment on it are insured separately.
The gear goes on tools and equipment insurance, an inland marine form covering welders, torches, gas cylinders, cutters and safety gear stolen from the truck or damaged at the job. Any welder, plasma cutter or other piece worth more than $2,500 may have to be scheduled on its own line, so keep serial numbers and purchase receipts in one file.
Repair work brings one more gap. When a customer’s truck frame or farm implement is damaged while you are welding on it, the general liability care, custody or control exclusion applies, because the equipment was in your hands. We ask insurers about bailee or customers’ goods coverage for repair welders who keep other people’s equipment in the yard.
C-60 licensing and when a mobile welder needs one
The CSLB’s C-60 Welding Contractor classification covers work that causes metals to become permanently attached, joined and fabricated using gases and electrical energy. Welding on real property, such as a structural repair, a gate post or a stair, needs a contractor’s license once the whole job, labor and materials together, passes $1,000, or whenever the work needs a permit. That minor-work line rose from $500 on January 1, 2025, and the exemption is not available to anyone who employs workers. Repair welding on trucks and farm machinery is not construction, so it generally sits outside CSLB licensing; confirm your own work with the CSLB.
C-60 is not yet on the CSLB list of classifications that must carry workers’ comp even without employees, and proof of coverage is due to the CSLB within 90 days of hiring a first employee. SB 216 and SB 1455 schedule a requirement for every licensee starting January 1, 2028; confirm the date with the CSLB as it nears. Our page on workers’ comp for sole proprietors covers the one-person case.
Welding class codes: 3365 or a fabrication class
WCIRB class 3365, Welding or Cutting N.O.C., shop or outside, covers fee-basis welding or cutting for others that is not connected with manufacturing, demolition, wrecking, salvage or construction. It includes repair of customer-supplied items primarily by welding, hardfacing and thermal-spray metallizing. Its pure premium rate is $5.289 per $100 of payroll from September 1, 2026. Welding done as part of building construction takes the construction class instead.
Shop fabricators are classed by product. Class 3030, structural iron or steel works, applies when structural work takes 50% or more of shop time, at $8.428. Class 3040, non-structural, covers ornamental iron, railings, balconies and staircases at $5.914. Class 3620(2) covers plate steel products when most of the metal is #9 gauge or heavier, at $6.620; 3066(1) covers light sheet metal products at $4.883; and laser or waterjet cutting for others falls under 3131(2) at $4.095. Each is a WCIRB pure premium rate per $100 of payroll, a benchmark rather than a premium. Labor Code 3700 requires workers’ compensation once you hire, and Labor Code 3722 sets a $1,500-per-employee penalty for going without. Our class code guide explains how the split is audited.
Certificates for general contractors and plant owners
Before a welder steps on site, general contractors and facility owners send insurance terms: additional insured status on the ISO CG 20 10 form or similar, primary and non-contributory wording, and a waiver of subrogation. Published purchase-order terms also ask for an ACORD 25 sent with a copy of the endorsement itself. Send us the contract’s insurance section before the bid closes. When the required limit sits above your general liability, a commercial umbrella fills the difference.
What welding insurance costs
Insureon’s welder cost page, updated August 13, 2026, reports national medians for welders who apply through it. They are published industry data, not California prices or a Mithril1 quote: general liability about $167 a month ($2,000 a year) at $1 million per occurrence and $2 million aggregate with a $500 deductible, workers’ comp $175 a month ($2,101), commercial auto $268 a month ($3,212), a business owner’s policy $125 a month ($1,503), tools and equipment $42 a month ($505), professional liability $67 a month ($808) and umbrella about $1,467 a year. Those are starting points for solo welders and small crews at standard limits; fabrication shops with structural work and larger payrolls pay well above them.
General liability tracks revenue and the type of work, workers’ comp tracks payroll by class, and auto tracks rigs and drivers. As a worked example, a mobile welder carrying Insureon’s median general liability, tools and commercial auto lands near $5,717 a year. Adding one welder at $60,000 of payroll in class 3365 adds about $3,173 at WCIRB’s $5.289 benchmark, before the insurer’s own rates and your experience modifier.
The premium goes up with hot work inside occupied buildings, structural steel and stairs for public spaces, contracts with high limits, older rigs and past fire or injury claims. It comes down with a written hot-work procedure and fire-watch logs, shop-only repair work, clean driving records, scheduled equipment with serial numbers and a short loss history. The insurer prices the actual file.
A few useful answers
Common questions
Does welding insurance cover a fire I start at a customer’s site?
General liability is the policy that responds to fire damage your welding causes to a client’s building or stored goods. Ask whether the quoted policy has a hot-work or fire-watch condition, and follow the NFPA 51B practice of a fire watch within 35 feet of combustibles, kept at least 30 minutes after the work.
Do I need a C-60 license as a mobile welder?
For welding on real property, yes, once the job passes $1,000 in labor and materials or needs a permit, or as soon as you employ workers. Repair welding on trucks and farm equipment is generally not construction. Check your own jobs with the CSLB.
Do I need workers’ comp if I weld alone?
Not yet as a C-60 with no employees, though the CSLB expects proof within 90 days of a first hire. A requirement for every licensee is scheduled for January 1, 2028, so check the date with the CSLB.
Which class code fits my metal fabrication shop: 3365, 3040 or 3030?
Fee-basis job and repair welding is 3365. A shop that sells railings, stairs and ornamental iron is usually 3040, and one doing structural steel at least half its shop time is 3030. The WCIRB footnotes and a payroll audit settle the final class.
How long after a job can a failed weld on a building lead to a claim?
California’s outer limit for latent construction defects is ten years from substantial completion under Code of Civil Procedure 337.15, so completed-operations coverage and weld records need to last that long.
Can a welding business insure both shop work and field work through Mithril1?
It can, once an insurer has reviewed your revenue split, rigs, equipment list and payroll by class. We request general liability, auto, tools and workers’ comp as one program so the certificate covers both kinds of job.