What Plumbing Services Require Special Licensing?

You may not have thought about it much before, but if you’re facing a major plumbing project you may be wondering, “What are the California plumbing license requirements?” Or perhaps, “Do I need a master plumber or someone with a special license for this job?”  So just what are the appropriate laws and precautions?  Well, it’s complicated.

All Plumbers

Pretty much all states require some sort of training and plumbing license for someone to legally be a plumber.  There’s 3 generally accepted levels or types of plumbers.  They relate to training and experience and only indirectly to what sorts of services they’re qualified to provide.  The exact requirements vary by state.

  • Apprentice Plumber — This is the starting position, with no special requirements.  They’re essentially a plumber’s helper or technician.
  • Journeyman Plumber –This designation requires 2-3 years of education, typically at a vocational school or community college, followed by 1-2 years as an apprentice then passing an exam.  Or the plumber can complete 3-5 years as an apprentice plus the exam.
  • Master Plumber — To become a master plumber requires 1-5 more years additional experience as a journeyman then passing an even more extensive and in-depth test.

Things Are a Little Different in California

Here it’s the contracting company, not the plumber, that must be licensed.  A contractor is the person or business that’s legally responsible for the work being done.  That can be an individual, a partnership, a joint venture, or a corporation.  So, often the “contractor” is the business owner who does some or all of the work.

Surprisingly, in the State of California there’s no license necessary to work as an apprentice or journeyman plumber and there’s no official designation for master plumber.  But to be legal all work totaling over $500 in materials and labor must be performed by a licensed contractor, with that license coming from the CSLB (California Contractors State License Board).

But you still want to hire someone with the right training and experience for the job you have.  And there are special contractor licenses for certain types of plumbing.

For general services including water pipes and storage tanks along with vents, flues, and connections for gas appliances (including water heater repair and installation) there’s a CSLB C-36 license.  There’s also a separate C-55 for installing water conditioners.

What About Sewer Lines?

Sewer cleaning usually isn’t a big deal.  But when a sewer line need repair or replacement, or for new installations there’s C-42.  This special license also applies to installing storm drains.

Gas Lines

Many jurisdictions require special license to work on gas piping.  That’s a good idea considering the potentially explosive results of a natural gas leak.  Repairing, upgrading the capacity, and installing gas lines are best left to a master plumber.  Most locations also require a city or utility company inspection after any work before the gas is turned back on.


There’s also a special CSLB license for work on boilers — C-4.  Often called a hot water heating contractors license, it’s needed for large commercial water heaters, boilers, and steam fitting.  These are complicated systems with the potential for a steam explosion, so an expert needs some very special training.

You can feel confident calling us or contacting us online. We are licensed, prompt and professional.