Running the Business · Part 6
Adding classifications: when to add the B, the C-20, or a second specialty, and how the exam waiver works
A C-36 can do plumbing and the work that is incidental and supplemental to it, and nothing else. The day a customer asks the plumber to replace the furnace with the water heater, or a remodeler asks for the whole bathroom, the answer is a second classification or a subcontract. This lesson is the map: what the C-36 covers and where "incidental" ends, what the C-20 adds and what a B or B-2 adds, the exam that a new classification normally requires, and the section 7065.3 waiver that lets an experienced qualifier add a closely related classification without one. It ends with the business question: which classification the market you are already in is asking for.
What the full lesson covers
- The C-36 covers plumbing as defined in 16 CCR 832.36; work in another classification is allowed only if it is incidental and supplemental to the plumbing job (16 CCR 830). Replacing the furnace is not incidental to replacing the water heater.
- Contracting for work outside your classification is contracting without a license for that work (B&P 7028), with the 7031 consequences for collection and the 7159 problems on top.
- A new classification normally requires passing its trade exam (7065); the waiver in 7065.3 requires five of the last seven years as a qualifier on an active license, four years of journeyman-level experience in the new classification within the last ten, and a finding that it is closely related.
- The B (general building) is for jobs with two or more unrelated trades or framing; the B-2 covers residential remodeling of existing structures with three or more unrelated trades; the C-20 adds heating and air conditioning, the most common second classification for a plumber.
- Change the business name (7059.1) and the advertising (lesson 2.6) only when the classification is actually on the license.
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More lessons in Growing the Business
- 1Hiring under AB 5: the ABC test, why a 1099 helper is a lawsuit unless they hold their own license, and the construction subcontract exemption
- 2Employees: wage and hour, overtime, meal and rest periods, final-pay rules, and the workers' compensation class code
- 3Apprentices and the Division of Apprenticeship Standards: how a small shop trains its next plumber lawfully
- 4Adding classifications: when to add the B, the C-20, or a second specialty, and how the exam waiver worksYou are here
- 5Systems: field-service software, the price book, and dispatch. What to buy, when, and what it must produce
- 6KPIs: average ticket, close rate, gross margin, and the three numbers that predict failure
- 7Supply-house credit at scale, the fleet, and inventory: the second truck's paperwork and the parts on it
- 8Becoming an RMO for someone else's company: the liability you are taking on, and the only version that is lawful
- 9Selling or stepping back: what a plumbing business is worth, what a buyer is actually buying, and what the license will and will not let you transfer
- 10Template: the hiring checklist (AB 5-safe), from the decision to the first day
- 11Template: the new-hire packet index
- 12Template: the monthly KPI sheet