how to get your C-2 insulation & acoustical contractor license in California

C-2 License Video: Insulation & Acoustical Contractor

Table of Contents

What Is a C-2 Insulation & Acoustical Contractor?

Insulation and acoustical contractor installs any insulating media and performs architectural acoustical materials for temperature and sound control – CSLB.ca.gov

A residential insulation set up

The C-2 License for Insulation and Acoustical Contractors covers a few different job titles include:

  • Soundproofing Contractors
  • Ceiling Contractors
  • Insulation Specialists
  • Home Insulation Contractors

These job titles are essentially interchange and all fall under the C-2 license for insulation and acoustical contractors.

Online Practice Exams and Study Guides Package

Duties of an Insulation Contractor

Insulation contractors engage in a wide variety of duties including:

  • Installing grid ceiling systems, insulated pipes and ducts, semi grid and thermal insulation boards
  • Installing batt, rigid board, and radiant barrier applications
  • Sealing buildings to stop air filtration
  • Soundproofing
  • Weather stripping
  • Erecting scaffolding, ladders and plants
  • Maintaining a safe job site
  • Estimation, bidding, accounting and preparing invoices

Getting the C-2 license will require that you have knowledge of all aspects of the insulation and acoustical trade.

A C-2 Insulation & Acoustical contractor legally is not allowed to bid on a project that falls outside of the spectrum of general insulation, acoustical construction, maintenance, or repair work.

C-2 License Requirements

To qualify for an exam date for the C-2 license you must meet the following requirements:

  • 18 Years of Age
  • Valid Drivers License or USA Issued Identification
  • Social Security OR ITIN Number
  • Cannot Currently be on Probation or Parole

You must also have:

  • 4 Years Journeyman Level Experience
  • Signature from a Qualifying Individual
  • Proof of experience if the state board requests

What is Journeyman Level Experience?

Journeyman-level experience means that you have worked unsupervised full time for a construction company, a contractor with the C-2 License, or a union.

The CSLB will want to see four full-time years of experience over the last ten years. The years do not need to be consecutive, but they do need to be four years in total. 

Signature Of A Qualifying Individual

A qualifying individual is someone other than yourself who can confirm your experience.

This person can be either a:

  • Licensed General Contractor
  • Licensed Insulation and Acoustical Contractor (C-2 License)
  • Fellow or Former Employee (within the last 10 years)
  • Foreman or Supervisor
  • Business Associate
  • Fellow Journeyman

Whoever you choose must include their information and a brief description of your experience.

The main areas of expertise an Insulation Contractor needs to have experience in are:

  • Installing Grid Ceiling Systems
  • Erecting Scaffolds and Ladders
  • Installing Sound Control Systems, pipes and duct work
  • Sealing Buildings to stop air infiltration
  • Insulating attics 
  • Weather stripping
  • Foil Reinforced Insulation 
  • Applied Polyurethane Insulation 
  • Insulated Pipes
  • Rolled Insulation Batts
  • Sprayed Foam

Filling out the C-2 License Application

When you are filling out your application to the CSLB, you must remember that the description your qualifying individual writes for you has to go into detail about your specific skill set.

Instead of just saying: John has insulated homes…”

The CSLB will want to see: John has installed grid ceiling systems, sealed buildings to stop air infiltration, installed weather stripping, soundproofed recording studios, etc. 

Insulation Subcontractor 

Insulation contractors that hold the C-2 license typically work directly with clients.

However, if they are working in a traditional construction setting they would function as a subcontractor under a company or individual who holds the General B license

an insulation contractor spraying purple foam between two wooden boards in an attic

  • Music and Entertainment Industry Clients
  • Soundproofing
  • Residential and Commercial Setting 
  • Optimizing Control Systems
  • Knowledge of Acoustics
  • Creating Sonically Balanced Rooms
  • Insulation and Acoustical Services

A General Contractor is in charge of the job from start to finish and must make sure that the insulation and acoustical portion of the project are completed to the specific requests of the client.

Proving your work experience for the C-2 License

You must be prepared to submit documentation supporting the experience you claim to have.

The Contractors State License Board gives you many ways to prove your experience including:

  • Tax Returns
  • Check Stubs
  • Contracts
  • Material Order Invoices or Receipts

The CSLB  receives thousands of applications per month.

So there is a good chance they won’t document your experience.

However, if you are one of the applicants that get reviewed you will need to be ready to submit something. 

The CSLB does not accept pictures of projects.

Application Processing, Fees, and Criminal History

The time it takes to get your application processed and assigned a test date fluctuates throughout the year.

Typically you can expect:

  • 6-8 Week Application Processing Time
  • 3-4 Week wait for an Exam date

I have seen some situations where applicants got their test date sooner and somewhere they got their test date much later.

The most common reasons your application would get held up are:

  1. Time of year (processing time slows down during the holidays) 
  2. Criminal History 
  3. Proving Experience
  4. Mistakes on your application 

Licensing Fees

  • State Application Fee – $330 

Can you get a contractors license with a Felony In California?
a wooden gavel laying on top of a wooden platform.

Having a criminal record in no way stops you from getting a C-2 License.

The key is, to be honest on the application, even if the felony or misdemeanor happened years ago and even if it was expunged.

BE 100% HONEST ON THE APPLICATION, because they will see everything anyway when you do fingerprinting. 

The CSLB handles criminal records on a case-by-case basis.

Remember, their responsibility is to protect the public. In my experience, they are primarily concerned with criminal charges associated with:

  • Fraud
  • Embezzlement 
  • Forgery 

In the state of California, you are required to divulge any criminal charges when applying for any state license even if they have been expunged.

You will need to be prepared to submit anything they ask for regarding your criminal history. 

Contractor Exam: C2 License

Contractor licenses are broken down into four categories:

1) A-General Engineering                            (LAW + TRADE )

2) B-General Building                                     (LAW + TRADE)

3) C-Specialty Classes                                    (LAW + TRADE)

4) C-61/D- Limited Specialty                     (LAW TEST ONLY)

The C-2 License Exam consists of two parts:

  • 115 Questions of Contractor LAW
  • 115 Questions on Insulation & Acoustical
  • 3 Hours To Complete Each Portion
  • Closed Book Exam

The Insulation and Acoustical (C-2 license) Examination is divided into four major sections:

1. Planning and Estimation (25%)

  • ·  Interpreting plans and specifications
  • ·  Planning
  • ·  Estimating

2. Acoustical (30%)

  • ·  Ceiling grid
  • ·  Acoustical tile and wall panels

3. Insulation (30%)

  • ·  Site preparation and blow-in applications
  • ·  Insulation preparation
  • ·  Batt, rigid board, and radiant barrier
  • applications

4. Safety (15%)

  • ·  Personnel safety
  • ·  Job site safety

CSLB Test Locations
logo of the contractors state license board. image features a hand saw, paint brush and cement truck with the letters CSLB above in white

Contractors State License Board

  • Oxnard
  • Sacramento
  • San Bernardino
  • San Diego
  • Berkeley
  • Fresno
  • Norwalk
  • San Jose

  • You have 18 months after your application is accepted to pass both examinations

  • You must wait 3 weeks to re-take the exam. $60 Per Re-take

  • You must score 70% or more

What is on the Law & Business portion of the Insulation & Acoustical Contractor License exam?

California Contractor License Exam Prep

a piece of graph paper with a pencil and calculator

  • The questions you will see on the exam may use outdated terms
  • Processes may be completely different from how things are done on the job site
  • You will see questions about things you may have never done before
  • Questions will be presented to you as if you are running a large scale construction business with several employees and jobs happening all at once. 
  • Know all aspects of your trade

Contractor License Practice Tests

Construction professionals from various backgrounds, trades, and experience levels get licensed in California each year.

In my experience, most are startled by how different the subject matter on the state exam is from their years of first-hand experience. 

Be as prepared as you possibly can.

Studying just 15 minutes a day consistently can dramatically increase your chances of passing the test on your first try.

Focus on and study ONLY the information that you need to pass the C-2 License exam. 

Construction Apprenticeships

A wall that is layered with yellow insulation.

If you don’t have the four years required journeyman level experience to obtain a C-2 License, not to worry.

Your journey begins here.

Construction is a trillion-dollar industry and highly skilled tradesmen are always in demand.

Whether you are completely new or have some home insulation experience already, there are resources available to you.  

Generally, someone looking to become an insulation contractor would want to look into an apprenticeship program.

For a detailed explanation of this process, check out my article: Apprentice vs Journeyman.

Blueprint Reading Course

a construction blueprint reading course

Like most construction trades, knowing how to read blueprints is very important.  

Correctly identifying elevations, ceiling, and wall plans to complete the insulation and temperature portion of their duties effectively.

Insulation contractors that aspire to hold a General Contractor License in the future will surely want to make sure their blueprint reading skills are up to par. 

Check out this Blue Print Reading Course for a basic introduction to the concepts you will want to know about.

EPA Certification

Logo of the Environmental Protection agency. Insulation contractors looking to get the C-2 license should get epa certified

Understanding how to safely contain lead-based paint when altering structures built before 1978 is required by the Environmental Protection Agency. 

The most profitable contractors are ones that position themselves as the experts and are the most knowledgeable and helpful to their clients.

Becoming EPA Certified is a requirement for insulation contractors and can be completed in a one-day, 8-hour course.

Staying EPA compliant is not only important to the survival of your business but also to the safety of your customers.  

For a complete guide on how to get the EPA Certification, check out this article.

Mold Certification

Working in a residential setting as an insulation & acoustical contractor, you may encounter mold.

Mold can create considerable problems for homeowners looking to protect the health of their families as well as the value of their property.

At some point, every property owner will require Mold remediation services. 

Mold caused by water damage can create long-term problems for any structure.

Getting a Mold Remediation Certification positions you to offer a needed service to a large customer demographic.

This article will detail everything you need to know about:

  • Mold
  • Health risks
  • Certifications 
  • State laws
  • Starting a Mold Remediation Business


Getting the C-2 License can be a huge step up in your career within the insulation industry! Whether you are trying to open your own company or become an RMO, there are several options.

The key is to take action and follow these steps from beginning to end.

If you have found this article helpful feel free to drop a comment below and be sure to check back for updates!