Colorado Plumber Job Site Inspections

Inspectors Can Check More Than the Plumbing

Most plumbers think of inspections as rough-in and final checks on the physical installation — pipe slope, fixture connections, pressure tests. In Colorado, inspectors have broader authority than that. Under House Bill 19-1086, plumbing inspectors can conduct "contemporaneous reviews" during any standard inspection. That means they can check the credentials of every plumber and apprentice working on the site.

This isn't theoretical. During a routine rough-in or final inspection, the inspector can request physical proof of licensure from every worker present. If you're a registered apprentice, that means your DORA registration card. If you're a licensed journeyworker or master, that means your current credential. If you're working for a contractor, the inspector can verify the contractor's registration and master plumber designation.

What Inspectors Look For

A contemporaneous review during a plumbing inspection typically covers:

License and registration verification. Every person performing plumbing work must hold a valid credential — apprentice registration, residential license, journeyworker license, or master license. The inspector can ask for proof on the spot. Carry your card or have your license number readily accessible.

Apprentice supervision compliance. If apprentices are on-site, the inspector verifies that a licensed plumber is supervising them in accordance with the rules. Under Board Rule 1.2E, the supervising plumber must be physically present at the permitted job address or located no more than five minutes' travel distance away. An apprentice working alone on-site with no supervisor within that radius is a violation.

Supervision ratios. For commercial installations, the supervisor-to-apprentice ratio is determined per individual permit. For residential work, the ratio covers the permitted structure plus one platted lot on either side. Exceeding the ratio is a code violation, even if the work itself is technically sound.

Contractor registration. The inspector can verify that the work is being performed under a valid, active contractor registration — and that the contractor's designated master plumber is current. If the contractor's registration shows "Need Master Hire — Cannot Practice," the project is non-compliant.

Consequences of Non-Compliance

If an inspector finds problems during a contemporaneous review, the response is procedural, not discretionary:

• Unlicensed workers: The inspector must halt the project and file an administrative complaint with DORA. The worker cannot continue, and the contractor faces potential disciplinary action.
• Unregistered apprentices: Same outcome — work stops, complaint filed. The employing contractor is responsible for ensuring every apprentice is registered within 30 days of hire.
• Supervision violations: If apprentices are working without adequate supervision (supervisor not within five minutes' travel, ratio exceeded), the inspector can halt the apprentice's work and flag the violation.
• Expired credentials: A worker with an expired license or registration cannot continue working. The contractor must either have the worker leave the site or produce another qualified worker to continue.

These complaints go through DORA's disciplinary process, which can result in fines, formal reprimands, license suspension, or revocation — consequences that affect both the individual worker and the contractor.

How to Stay Compliant

Job site compliance is straightforward if you plan for it:

Carry your credentials. Every plumber and apprentice on-site should have their registration card or license number readily available. Don't leave it in the truck at the other site.

Know the supervision distance. If you're supervising apprentices, stay within five minutes' travel of the permitted address. The old "same general area" standard is gone — the current rule specifies proximity at the permitted site.

Verify your contractor's status. If you're employed by a contractor, periodically check their registration status through DORA's online lookup tool. If the contractor's registration lapses or enters "Need Master Hire" status, work performed under that registration is non-compliant and the business must correct the status before resuming operations.

Track apprentice registrations. If you're a contractor, confirm that every apprentice has been registered within the 30-day window. An unregistered apprentice on a job site during an inspection is a direct violation that triggers a mandatory complaint.

The Colorado Plumber License Guide covers the full supervision framework, inspection protocols, and compliance requirements — so you can plan for job site reviews before they happen, not scramble when an inspector shows up.

See more Colorado guides →