Colorado Plumber Experience Verification: Documenting Your Hours for DORA

Experience verification is the most common sticking point in Colorado's plumbing license application process. The hours themselves are straightforward — 3,400 for residential, 6,800 for journeyworker, 8,500 for master — but proving you earned them requires documentation from every employer you've worked under. When a former boss has retired, moved, or simply won't return your calls, the process gets complicated fast.

How DORA Counts Hours

The State Plumbing Board uses a fixed formula: one month of full-time plumbing work equals exactly 163 hours. This conversion rate applies universally, regardless of how many hours you actually worked in a given week. If your employer reports 12 months of full-time employment, DORA credits you with 1,956 hours.

All hours must be earned while working under the direct supervision of a licensed plumber and while employed by a registered plumbing contractor. Side work, unlicensed employment, and hours worked for unregistered contractors don't count — even if the work itself was legitimate plumbing.

The Affidavit Requirement

When you apply for any license tier (residential, journeyworker, or master), your application package must include notarized Affidavits of Experience from every employer whose hours you're claiming. These affidavits must be signed by the supervising Master Plumber or the registered plumbing contractor; if that person is unavailable, a co-owner or office manager on company letterhead may verify the hours. You cannot sign the affidavit yourself.

The affidavit must confirm:

• The dates you worked for the company
• The total hours of plumbing experience accumulated
• The type of work performed (residential, commercial, industrial)
• The name and license number of the plumber who supervised your work

The Self-Verification Ban

Board Rule 1.4 A(3)(f) prohibits applicants from verifying their own work experience under any circumstances. This applies even if:

• You currently hold an active license in another state
• You operated as a sole proprietor with your own clients
• You're a business owner who also works in the field

This is a hard rule with no exceptions. If you've been running your own operation in another state, you still need a third party — a co-owner, a licensed supervisor who observed your work, or a former employer — to sign the affidavit.

When a Former Employer Won't Sign

This is the scenario that causes the most anxiety, and it's more common than you'd think. Employers go out of business, owners retire, or relationships end on bad terms. Here's what the system provides:

Co-owners and office managers can verify hours on company letterhead if the original supervising plumber is unavailable. The verification must still come from someone with direct knowledge of your employment.

DORA's annual apprentice reporting database is a backup source. Registered plumbing contractors are legally required to report apprentice hours to the State Plumbing Board every January 1. If your former employer reported your hours as required, those records exist in DORA's system and can be used as official verification.

Supporting documentation like W-2 forms, tax records, and pay stubs can help establish employment dates and duration, though they don't replace the affidavit requirement. They're most useful when combined with database records to build a complete picture.

If none of these avenues produces a verification and your former employer is genuinely unreachable, do not assume that a written explanation or corroborating documents will replace the affidavit. No automatic substitute is identified, so confirm the acceptable path with DORA before filing.

Trade School and Military Credits

Two pathways can offset a portion of the field hour requirements:

Trade school: Graduates of accredited two-year vocational programs, community colleges, or high school plumbing programs can receive credit at a rate of one classroom hour equals one field hour, up to a maximum of 2,000 hours (approximately one year of field work). You'll need to submit official academic transcripts to DORA for evaluation.

Military experience: Plumbing training in the U.S. Armed Forces is credited at one month of practical field experience for every six months of documented military plumbing training, capped at one year of total credit. Submit your military training records and any plumbing-related MOS documentation.

Both types of credit reduce the remaining field hours you need to verify through employer affidavits — they don't eliminate the affidavit requirement entirely.

Out-of-State Experience

If you earned your hours outside Colorado, the same affidavit requirements apply — your out-of-state employers must verify your experience on letterhead or through DORA's experience forms. A photocopy of your active out-of-state license is required as part of the application, but it doesn't substitute for employer-verified affidavits.

If your out-of-state experience includes a state or federally approved apprenticeship program, submit verification of completion. DORA evaluates the equivalency of out-of-state programs on a case-by-case basis.

Start Tracking Before You Need To

The verification process is dramatically easier if you maintain your own records from day one. Keep a running log that includes:

• Dates of employment and hours worked per week
• The name, license number, and contact information of every supervising plumber
• The contractor registration number of every employer
• Types of work performed (residential new construction, commercial tenant improvement, service and repair)

When it's time to apply, you'll already know exactly who needs to sign what, and you'll have the supporting documentation to fill in any gaps.

The Colorado Plumber License Guide includes a fillable Experience Affidavit Tracker built around DORA's 163-hour monthly formula, so your personal records map directly to the totals the Board needs to see on your application.

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