how to get your C-61 contractors license to install central vacuum systems in California

Central Vacuum Systems: C-61/D-4 License

Table of Contents

What is a Central Vacuum System?

A Central Vacuum System is a device that is installed in a building that collects dust particles and debris through tubes.

  • The dust is stored in a remote place and can be cleaned manually. 
  • Central Vacuum Systems are widely considered to be a healthier alternative to traditional vacuums. 

Studies conducted by the Environmental Protection Agency as well as  UC Davis have proven the benefits of central vacuum systems in preventing allergies and respiratory problems.

A remote storage unit for the dust and debris collected by a central vacuum system

“Using central vacuum systems that are vented to the outdoors can significantly reduce dust mites, pollen, animal dander, and other allergy-causing agents.” – U.S. Environmental Protection Agency

Study Conducted by UC Davis on the health benefits of Central Vacuum Systems

What is a Central Vacuum Systems Contractor?

A central vacuum systems contractor installs, modifies, maintains or repairs central vacuum systems, pneumatic tube dispatching systems or any other type of pipeline which operates systems of reduced pressure for any purpose” – CSLB.GOV

The C-61/D-4 license is in the state of California for all persons looking to bid on all projects involving awnings where the cost of labor and materials exceeds $500.

C-61 Limited Specialty Classification

The C-61 Limited Specialty License is an umbrella term for all licenses that may fall under a more obscure category of construction work.

They cover specific areas of construction and construction-related tasks. 

If your skillset or business is limited to one particular portion of trade work, you could obtain a C-61 limited specialty license to contract over $500 for your services legally.

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Typical duties associated with Central Vacuum Repair and Installation

Companies that specialize in central vacuum installation and repair typically engage in duties including:

  • Central Vacuum installation, repair and maintenance 
  • Cleaning power units and filters
  • Identifying inlet problems
  • Checking low voltage connections
  • Inspection of hose and connections
  • Cleaning clogs in the hose
  • Job site and property assessment
  • Maintaining relationships with suppliers for replacement parts
  • Trouble shooting and assessing functionality of central vacuum systems
  • Estimation, cost calculation, bidding and accounting
  • Ensuring a safe job site
  • Light carpentry

Central Vacuum Subcontractor

Vacuum contractors typically work directly with small businesses or homeowners. However, they may also function as subcontractors as part of a larger construction project.

In a construction setting, a General Contractor hires a vacuum installation specialist. Perhaps a client has requested a specific customized central vacuum system as part of their construction or remodel.

As a result, a general contractor ensures that the central vacuum installation is executed in adherence to safety codes.

Learn more about the General Contractor License!


logo of the CSLB, which is the governing agency for contractors in the state of california. Contractor license law is essentially set by the CSLB

The Contractors State License Board (CSLB) is the governing body for all contractors in the state of California. Their sole responsibility is to protect the consumer public. 

They ensure that anyone charging over $500 for construction services is qualified and registered with the state.

The C-61 / D-4 central vacuum systems contractor license is issued to contractors by the CSLB. 

EPA Certification

Logo of the united states environmental protection agency

When making alterations to or around structures built before 1978, contractors must know how to contain lead paint if it is present.  

Lead paint can travel miles through air, rest on soil, and enter air ducts causing potentially fatal respiratory damage.

Central vacuum contractors looking to build profitable businesses must position themselves as experts and the authority within their industry. 

Central vacuum installation specialists must be a source of information for their clients and community if they want referrals and repeat business. Learn how to get an EPA Certification in 8 hours!

Blue Print Reading Course

featured image for a blog post about how to read construction blueprints

It is critical for central vacuum contractors to be able to read designs and symbols on construction blueprints.

If installation or repair is part of a larger project, being able to execute their duties within the larger scope of the job is essential. 

Reading blueprints is an invaluable skill for all tradesmen but can be especially important for central vacuum contractors.

Check out our Free Blueprint Reading Course!

C-61 / D-4 Central Vacuum Contractor License Requirements

Central Vacuum Contractors in California must prove a minimum of 4 years of journeyman level experience and pass a law exam.

To qualify for an exam date you must meet the following requirements:

  • Be at least 18 years of age
  • Have a valid Driver's License or USA Issued Identification
  • Have a Social Security or ITIN #
  • check Not Currently be on probation or parole

You must also have:

  • 4 Years Journey Level Experience 
  • A Certifier to sign off on your experience
  • A way to prove your experience if the state asks for documentation

What is journey level experience?

A heavy duty street cleaning vacuum system being used by a civil service worker on the street after a parade

Journeyman-level experience means that you have worked unsupervised full-time for a central vacuum company, or for a contractor that holds the D-4 License.

  • A journeyman can perform all of the duties associated with his or her trade.

The CSLB will want to see four full-time years 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 Certifier

The following people may act as a certifier when applying for your Central Vacuum License

  • Licensed General Contractor
  • C-61 / D-4 Central Vacuum License Holder
  • Former Supervisor (within the last 10 years)
  • Fellow Employees (within the last 10 years)
  • Business Associate
  • Fellow Journeyman
  • Union Representative

How to fill out the Contractor License application

In addition, your Qualifying Individual will need to provide a brief but detailed description of your knowledge and skillset.

The way this description is written is critical to whether or not your application gets accepted.

For example: 

“Ted installed our vacuum system and now the air is great” is not descriptive enough.

The CSLB will want to see something like: 

Ted has conducted in-home inspections, installed, serviced, and maintained central vacuum systems. Identified vacuum clogs, has used central vacuum hoses, conducted tests and troubleshot existing vacuum systems” etc.

Most importantly, the description written by your qualifying individual has to include the core skills required by a central vacuum contractor.

​​​​Work experience for the Contractor License

a vacuum cleaning a rug. when applying to the CSLB for a contractor license, they may ask to see documentation of your experience

You must be prepared to submit documentation supporting the experience you claim to have. The Contractors State License Board gives you a few ways that you can prove your experience which include:

  • 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 

Contractor License Costs

The Current CSLB fees are: 

Can you get a Contractor's License with a Felony in California?

a wooden gavel laying on top of a small wooden platform

Having a criminal record in no way stops you from getting a central vacuum Contractor License. Thousands of tradesmen get licensed each year despite having criminal records, some of whom obtain multiple licenses.

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

See the CSLB's verbiage below:

Just because you have been convicted of a crime does not automatically mean
your application will be denied. CSLB's Criminal Background Unit (CBU) reviews
all criminal convictions to determine if the crime is substantially related to
the duties, qualifications, and/or functions of a contractor. Since no two
conviction records are the same, they are reviewed on a case-by-case basis. The
criteria used by CSLB include whether the crime shows the present or potential
unfitness of an applicant or licensee to perform the functions authorized by
the license in a manner consistent with the public health, safety, or welfare.
In addition, CSLB reviews and considers any evidence of rehabilitation
submitted by the applicant or licensee. Please see the above link to the
California Code of Regulations sections 868 and 869 for more specific
information on the criteria for determining substantial relationship and

more about the Background Check Process here:

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. Typically the CSLB is most concerned with Fraud, Embezzlement, and Forgery.

The Contractor License Exam

Contractor licenses are broken down into four categories:

1) A-General Engineering

2) B-General Building

3) C-Specialty classes

4) C-61 / D-Limited Specialty classes

Each category of license except the D-Limited Specialty license class requires that you pass a TRADE exam. C-61 Classification licenses do not have trade portions.

You must only pass a LAW exam.

The exam is:

  • 115 Questions on Contractor LAW
  • 3 hours to complete
  • Multiple choice, taken on a computer
  • check Closed Book

The Law Examination is divided into eight major sections:

  1. Business Organization and Licensing (13%)

  • Company organization
  • Licensing requirements
  • Advertising and subcontracting

  1. Business Finances (15%)

  • Cash management
  • Budget and planning
  • Taxes
  • Financial reporting

  1. Employment Requirements (20%)

  • Hiring employees
  • Supervising and training employees
  • Evaluation and record-keeping
  • Payroll

  1. Insurance and Liens (12%)

  • Workers’ compensation insurance
  • Business Insurance
  • Liens and other remedies

  1. Contract Requirements and Execution (21%)

  • Bidding
  • Cost control
  • Project organization
  • Contracts
  • Payments

  1. Public Works (5%)

  • Prevailing wage requirements
  • Bonding requirements
  • Insurance requirements

  1. Safety (14%)

  • Training and reporting requirements
  • General safety
  • Hazardous/unknown materials

Learn more about Contractor License Law!

CSLB Test Locations

There are CSLB testing locations all over California.

The CSLB has exam centers all over the state of California. Once your
application is approved you will be given a list of locations you can go and
take the exam based on your zip code.

These are proctored facilities with cubicles where you take the exam on a
computer. The computer will have a calculator for your use. You will not be
able to bring in a phone, notes, or personal calculator to the exam center.

California Contractors License Exam Prep

a pencil and a calculator laying on top of a sheet of grid paper with some writing on it

  • Getting your central vacuum systems contractors license is a smooth process if you have the right information. 

  • It can be confusing to see unfamiliar terms used to describe tools or job site practices. The Contractor LAW exam covers a number of different topics.

  • Questions are presented to you as if you are running a large-scale remodeling business with multiple employees.

  • Being prepared and knowing what to study is the most important thing you can do in ensuring your success on the contractor license exam.

Construction Apprenticeships

A construction worker wearing a gold tool belt with several tools inside. Also he is holding a red hard hat, wearing a blue checkered shirt

If you do not have the experience required to get the C-61/D-4 Central Vacuum systems Contractor license, not to worry!

Your journey begins here. Generally, someone looking to become a vacuum systems contractor would want to look into an apprenticeship to find an experienced person to work with.

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