New Hampshire Mechanical Inspection

Two Inspection Authorities, One Project

New Hampshire splits mechanical inspection authority between local building departments and the State Fire Marshal's Office. Which one handles your HVAC installation depends entirely on where the project is located — and getting this wrong can leave a completed job in legal limbo.

Cities and towns with their own code enforcement staff handle inspections locally. Manchester, Nashua, Concord, and most mid-size towns fall into this category. The local building inspector reviews permit applications, conducts rough-in and final inspections, and issues completion approvals.

In unincorporated areas or jurisdictions without local code enforcement authority, the State Fire Marshal takes over. This is a state-level function administered through the Department of Safety's Division of Fire Safety — not the OPLC, which handles licensing but not on-site inspections.

The State Fire Marshal's Building Permit Program

When the Fire Marshal has jurisdiction, you'll submit project notifications through the MyGov portal rather than a municipal office. The permit fee is calculated at 1.2% of the first $100,000 of contracted construction cost — a different model from the flat or unit-based fees that cities charge.

The Fire Marshal's inspectors cover a large geographic territory, so scheduling is less flexible than dealing with a local building department. Plan for longer lead times between requesting an inspection and getting one on the calendar, particularly during peak construction months.

Key points about Fire Marshal inspections:

• Rough-in inspections must happen before closing walls or concealing ductwork. The inspector needs to see gas piping, venting, and duct connections before they're hidden behind drywall.
• Final operational inspections verify that the completed system runs safely and meets code. The system cannot be permanently commissioned until this sign-off is complete.
• The project is not legally finished until the inspector issues final approval or the municipality issues a certificate of occupancy.

The OPLC Is Not an Inspection Authority

A common point of confusion: the OPLC licenses technicians and businesses, but it does not inspect installations. When a contractor says "I'm OPLC-licensed," that certifies their professional competency — it says nothing about whether a specific project has been inspected and approved.

The OPLC can and does investigate complaints about unlicensed work or code violations, and it can issue Notices of Violation or suspend licenses under RSA 310:12. But the actual on-site inspection of your installation is always handled by either the local building department or the State Fire Marshal, never by the OPLC itself.

What Inspectors Look For

Whether local or state, mechanical inspectors evaluate HVAC installations against the state-adopted International Mechanical Code (IMC) and applicable NFPA standards. Common inspection items include:

• Gas piping pressure testing and leak checks
• Proper clearances from combustible materials
• Venting system sizing and termination locations
• Combustion air supply adequacy
• Electrical connections and disconnect accessibility
• Equipment manufacturer installation requirements
• Code-compliant condensate drainage

Gas piping installations get particular scrutiny. Under Amilia's Law, the consequences of improper gas work are well understood by inspectors, and failed gas inspections require correction and re-inspection before approval.

Scheduling and the Permit Workflow

The practical workflow for any HVAC project in New Hampshire follows this pattern:

1. Pull the permit from the local building department or Fire Marshal
2. Perform the installation
3. Schedule a rough-in inspection before concealing work
4. Receive rough-in approval (or correction notice)
5. Complete the project
6. Schedule the final inspection
7. Receive final approval or certificate of occupancy

Skipping any step — particularly the rough-in inspection — can result in the inspector requiring you to open walls to expose previously concealed work for review. That's an expensive mistake that falls on the contractor, not the homeowner.

The Contractor's Responsibility

As the licensed contractor, scheduling inspections is your obligation, not the property owner's. Municipal stop-work orders and OPLC enforcement action both target the contractor's license, not the customer. Building a reliable inspection scheduling process into your project management workflow prevents the most common compliance failures new contractors encounter.

The New Hampshire HVAC License Guide covers the complete permit-to-inspection sequence for both municipal and Fire Marshal jurisdictions, including the specific documentation each authority expects.

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