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Resolve the property
Match the address to its parcel, zoning context, and responsible permit authority.
What we check
What a mechanical permit application usually needs
Equipment Scope
Reviewers need to know whether the work is replacement, new installation, relocation, fuel conversion, added capacity, or a new HVAC zone. Furnaces, boilers, air handlers, condensers, mini splits, heat pumps, exhaust fans, and fireplaces can each trigger different review.
Furnace Replacement and Fuel-Gas Work
A furnace replacement can trigger checks for gas piping, shutoffs, sediment traps, venting, combustion air, condensate, electrical connection, and equipment sizing. Some AHJs require a licensed mechanical or HVAC contractor to pull the permit.
Air Conditioner, Heat Pump, and Mini Split Systems
An air conditioner, heat pump, or mini split permit may require equipment location, condenser pad details, noise or setback checks, refrigerant-line routing, electrical disconnect, condensate disposal, and final inspection.
Ductwork, Exhaust, and Venting
New or altered ductwork, bathroom fans, kitchen exhaust, dryer exhaust, combustion venting, and make-up air can trigger review because they affect fire safety, moisture, pressure, and indoor air quality.
Load, Energy, and Manufacturer Data
Some applications ask for equipment make and model, BTU capacity, efficiency rating, Manual J or sizing notes, duct layout, gas load, or manufacturer installation instructions before approval.
Inspection and Closeout
Mechanical permits often close with rough and final inspections. Inspectors may check equipment access, clearances, vent termination, gas piping, condensate, electrical disconnects, duct sealing, combustion air, and startup documentation.
Process
Why Mechanical Permits Get Missed
Homeowners often search HVAC permit or furnace replacement permit, while the AHJ may call the same approval a mechanical permit. The safest workflow is to confirm the local label, licensed-contractor rule, and inspection sequence before equipment is ordered or installed.
Per state
State-specific notes
IL
Illinois
Illinois mechanical permit requirements are local. Cities and villages may require contractor registration, HVAC licensing, separate electrical permits, gas-pressure checks, or final inspection before closeout.
Explore Illinois permit rules
WI
Wisconsin
Wisconsin mechanical work can involve local permits, UDC-adjacent residential expectations, HVAC contractor rules, energy details, and inspection sequencing depending on equipment type and project scope.
Explore Wisconsin permit rules
IN
Indiana
Indiana requirements vary by city and county. Many AHJs require mechanical or HVAC permits for furnace replacement, AC units, mini splits, gas piping, ductwork, and remodel equipment changes.
Explore Indiana permit rulesWatch for these
Common mechanical permit mistakes
- Assuming an HVAC swap is always exempt because the equipment location stays the same
- Missing a separate electrical permit for disconnects, circuits, or panel work
- Installing equipment before confirming licensed-contractor or registration rules
- Ignoring venting, combustion air, condensate, or make-up air requirements
- Forgetting that exterior condensers or mini splits can trigger zoning, noise, or setback checks
Next permit paths
Related permit guides
HVAC permit guideFurnace replacement, AC installation, mini splits, heat pumps, ductwork, gas work, and inspections.Open guideAir conditioner replacement permit guideOutdoor condenser placement, refrigerant lines, electrical disconnects, condensate, contractor rules, and final inspection.Open guideMini split permit guideOutdoor condenser placement, refrigerant lines, electrical disconnects, condensate, contractor rules, and final inspection.Open guideFurnace replacement permit guideGas piping, venting, combustion air, electrical connection, contractor rules, and final inspection.Open guideElectrical permit guideCheck when HVAC equipment, disconnects, new circuits, panels, or service changes need electrical review.Open guideWater heater permit guideFor equipment that crosses plumbing, mechanical, gas, venting, combustion air, and inspection rules.Open guideBuilding permit requirementsUse the broad permit path when mechanical work is part of a remodel, addition, basement finish, or larger project.Open guideManaged permit helpUse Permitech when HVAC work needs address-specific AHJ research, contractor-rule checks, or filing guidance.Open guide
Done for you · from $199
Check the Mechanical Permit Path Before Equipment Install
Our permit experts research the AHJ requirements for your address, including mechanical permit triggers, HVAC contractor rules, equipment documentation, gas or electrical coordination, venting and combustion-air checks, and inspection sequencing.
Our DIY Permit Package currently covers sheds and garages. For mechanical permits, our Done-For-You team handles the research and filing guidance.
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For contractors
HVAC Contractors: Turn Local Permit Rules Into a Repeatable Checklist
Mechanical permitting changes by AHJ, equipment type, fuel source, license rules, electrical scope, and inspection practice. Use Permitech to standardize the local path before crews schedule installation.
Our self-serve subscription plans currently cover sheds and garages. For mechanical permits and other project types, we work with contractors on a custom contract basis tailored to your volume and service area. Fill out the quote form above and select "Contractor", and we’ll put together a plan that fits your operation.
Request a custom contractor quote500+ permits per year, in person
Built by a former permit tech who processed 500+ building permits per year across IL, WI, and IN. We don't just check if you need a building permit, we check zoning too.