Skip to main content
PermitBase

Mechanical / HVAC Permit in Unincorporated Natrona County, Wyoming

Required for heating, cooling, and fuel-gas appliance installations in unincorporated Natrona County. Governed by the 2024 International Mechanical Code (IMC, Resolution 88-24) and 2024 International Fuel Gas Code (IFGC, Resolution 87-24).

Verified 2026-07-01 · Source

When you need this permit

  • Mechanical Permit Application submitted to the Natrona County Building Department
  • Specify Applicant Type (Owner/Contractor) and fuel type (Natural Gas, Liquid Propane Gas, Other)
  • Disclose whether work is being done on Casper/Natrona County Airport property (special jurisdiction flag on the form)
  • Nature of Project: New Construction, Basement Finish, New Installation, or Replacement
  • Quantity and type of appliance must be listed: A/C (tonnage), mini-split (tonnage), boiler (BTU), refrigeration units (tonnage), furnace (BTU), pellet stove, wood stove, gas fireplace (BTU), unit heaters (BTU), infrared/tube heat (BTU), commercial air handler (CFM), wall heater (BTU), residential/commercial clothes dryers, evaporative cooler
  • Job valuation must be declared for fee calculation

Required documents

Check off what you have — your progress is saved on this device.

Not ready yet — 0 of 1 required documents checked.

This checker covers one permit. A full project usually triggers several — our checklist will assemble all of them, free →

Fee schedule

Mechanical Permit Fee — valuation-based (same table as building permits)Natrona County Permit Fees, Resolution No. 45-20 — mechanical/HVAC has no separate flat fee; uses the same combined valuation-based schedule.
$70 (valuation $0–$2,500) up to $905 plus $9.24 per additional $1,000 over $98,000
Mechanical Contractor License — InitialNatrona County Contractor Fees (Revised 02/21)
$300 (Contractor); $75 (Master); $25 (Journeyman); $3 (Apprentice)
Mechanical Contractor License — Annual Renewal
$75 (Contractor); $37.50 (Master); $15 (Journeyman); $3 (Apprentice)

Review timeline

Plan reviewTypical estimate — confirm current times with the Unincorporated Natrona County building department
~3–10 business days

How long did your Mechanical / HVAC Permit permit actually take in Unincorporated Natrona County?

Anonymous — one question, no email. Answers are combined and only shown once at least 5 people have reported.

Inspection process

  1. 1

    Rough-In / Equipment

    Equipment placement and ductwork/venting before walls closed

  2. 2

    Final

    Equipment operational, combustion air and venting verified

See the full Unincorporated Natrona County inspection guide — scheduling & re-inspection fees →

Tips

  • Work on Casper/Natrona County Airport property is specifically flagged on the mechanical application — airport-area projects may involve additional coordination beyond the standard county permit process.
  • The mechanical application itemizes appliance types by tonnage/BTU/CFM — have your equipment specs ready when applying.

Frequently asked questions

Yes. Furnace replacement is a 'Replacement' project type on the county's Mechanical Permit Application, requiring the furnace's BTU rating. The permit fee follows the same valuation-based table as all other trade permits (Resolution No. 45-20).

In Unincorporated Natrona County, the published Mechanical Permit Fee — valuation-based (same table as building permits) is: $70 (valuation $0–$2,500) up to $905 plus $9.24 per additional $1,000 over $98,000. Additional published fees: Mechanical Contractor License — Initial — $300 (Contractor); $75 (Master); $25 (Journeyman); $3 (Apprentice); Mechanical Contractor License — Annual Renewal — $75 (Contractor); $37.50 (Master); $15 (Journeyman); $3 (Apprentice). These are the jurisdiction's own published figures — see the fee schedule table and source citations on this page.

Plan review for a mechanical / hvac permit in Unincorporated Natrona County typically runs 3–10 business days. This is an estimate, not a published figure — confirm current review times with Natrona County Building Department at (307) 235-9435.

You'll need: Natrona County Mechanical Permit Application (2025). See the required-documents checklist on this page for details on each.

Unincorporated Natrona County requires 2 inspection(s) for a mechanical / hvac permit, in order: Rough-In / Equipment, Final. Schedule each through Natrona County Building Department ((307) 235-9435).

Apply through Natrona County Building Department at 200 N. Center St, Room 205, Casper, WY 82601. Phone: (307) 235-9435, email: Contact via natronacounty-wy.gov (email obfuscated on site; call 307-235-9435). Office hours: Monday–Friday, 8:00 AM–5:00 PM. Official information: https://www.natronacounty-wy.gov/170/Building-Inspection.

Unincorporated Natrona County, Wyoming has adopted: 2024 International Building Code (IBC) — adopted by Resolution 84-24; 2024 International Residential Code (IRC) — adopted by Resolution 90-24; 2024 International Existing Building Code (IEBC) — adopted by Resolution 85-24; 2024 International Fire Code (IFC) — adopted by Resolution 86-24; 2024 International Fuel Gas Code (IFGC) — adopted by Resolution 87-24; 2024 International Mechanical Code (IMC) — adopted by Resolution 88-24; 2024 International Plumbing Code (IPC) — adopted by Resolution 89-24; 2023 National Electrical Code (NEC / NFPA 70) — adopted by county resolution. Local amendments apply — see the Unincorporated Natrona County overview page for the full list.

Sources & verification

Verified against official sources. Last reviewed 2026-07-01.

Fees, timelines, and adopted codes are researched from each jurisdiction's published records — see how we verify. Requirements change and vary by project, so always confirm the current details with the Unincorporated Natrona County building department before you submit. PermitBase is an independent reference and is not affiliated with any government agency.

Other permits in Unincorporated Natrona County

Residential Building Permit (New Construction)Residential Addition / Remodel PermitElectrical PermitPlumbing PermitRoofing Permit (Reroof)Solar PV PermitAccessory Dwelling Unit (ADU) PermitDemolition PermitCommercial Tenant Improvement PermitDeck PermitEV Charger / EVSE PermitSign PermitFire Alarm System PermitFire Sprinkler System PermitChange of Use / Zoning Certificate & Certificate of Occupancy

Mechanical / HVAC Permit in other cities

Casper, WyomingCheyenne, WyomingEvanston, WyomingGillette, WyomingGreen River, WyomingJackson, WyomingLaramie, WyomingRiverton, Wyoming

Compare mechanical / hvac permit fees across Wyoming →

Look up this fee in a different city →

Embed this data card →

Related guides

Furnace Replacement

Now live

Build your Unincorporated Natrona County project checklist

Describe your project once and get every permit, document, and fee it triggers in Unincorporated Natrona County — in one checklist. Sign up and pay once to generate it, or go unlimited with Pro.

Get started →