What's Required in Chicago
- In-kind repair or replacement of a furnace, boiler, radiator, ductwork or air conditioning appliance at a residential building up to 4 stories needs no permit.
- Replacing equipment with a different type or energy source, adding new air conditioning or a heat pump, or extending ducts or gas piping requires an express mechanical permit.
- New equipment must meet the minimum efficiency requirements of the Chicago Energy Transformation Code and the application includes the energy and water efficiency compliance form.
- New air conditioning or heat pump equipment requires an HVAC load calculation and a scaled site plan.
- Rooftop or truss-mounted equipment requires a structural evaluation letter from an Illinois-licensed architect or structural engineer.
- The permit lists a licensed general contractor unless the owner qualifies to act as contractor on their own primary residence.
- Any hardwired electrical connection or new circuit requires a separate electrical permit filed by a Chicago-licensed electrical contractor.
- Refrigerant work must be performed by EPA Section 608 certified technicians and gas piping must be tested under Chapter 4 of the 2021 International Fuel Gas Code.
- New outdoor equipment may not exceed 55 dB(A) at 100 feet or 70 dB(A) at 10 feet.
Do You Need a Permit to Replace a Furnace or AC in Chicago?
Not for a like-for-like swap at a house or small building. The Department of Buildings' list of work that needs no permit says that in a residential building up to 4 stories above grade you may repair or replace in-kind a furnace or an element of an associated heating system, such as ductwork, a boiler or radiator, or an air conditioning appliance. In-kind means the same type, size and shape, so a new gas furnace in place of the old gas furnace, or a new condenser of the same size on the same pad, needs no building permit. On any building, repairing an appliance, replacing parts without changing its function or efficiency, and installing portable cord-and-plug heating, cooling or ventilation equipment or a domestic cooking appliance are also exempt.
The permit line is crossed when the equipment changes function or something new is added: a heat pump replacing a furnace, central air where there was none, a bigger unit, new or rerouted ductwork or gas piping, or any replacement in a building taller than 4 stories or with a non-residential occupancy. Those jobs use the Mechanical (HVAC) Work worktype in the Express Permit Program, which launched November 6, 2023, and which explicitly allows replacing equipment with equipment performing the same function even when the energy source changes, and installing a new heat pump or air conditioning system for a single unit based on a load calculation. Equipment that misses the Chicago Energy Transformation Code efficiency minimums is not eligible.
Chicago HVAC Permit Rules by Scenario
| What you are doing | City filing | Rule |
|---|---|---|
| Replacing a furnace, boiler or AC in kind at a home up to 4 stories | None | DOB list of work not requiring a permit (Mechanical) |
| Repairing an appliance or replacing parts, any building | None | DOB exemption list (Mechanical) |
| Window unit, space heater or other cord-and-plug appliance | None | DOB exemption list (Mechanical) |
| Replacing equipment with a different type or energy source (furnace to heat pump) | Express mechanical permit, $75 per equipment type; energy form | EPP Mechanical; Table 14A-12-1204.2 |
| Adding central AC or a heat pump where there was none | Express mechanical permit, $150 per dwelling unit, load calculation and site plan | Table 14A-12-1204.2; EPP Mechanical |
| Extending or rerouting ductwork or gas piping | Express mechanical permit, $75 per dwelling unit each, HVAC drawing | Table 14A-12-1204.2 (current compiled table) |
| New circuit or disconnect for the equipment | Separate electrical express permit, $150 for up to 10 new circuits, licensed electrical contractor | Table 14A-12-1204.2 (Electrical) |
How Much Does an HVAC Permit Cost in Chicago?
Nothing for an exempt in-kind replacement. When a permit is needed the fees are flat stand-alone fees in Table 14A-12-1204.2 of the Administrative Provisions: repair or in-kind replacement of heating, cooling or air-handling equipment, $75 per equipment type and per dwelling unit; installation of new equipment for air conditioning, $150 per dwelling unit; duct extension or reconfiguration, $75; and, in the current compiled table, gas piping extension or reconfiguration, $75 per dwelling unit. Fees stack when a permit covers more than one listed scope, so a new central air system with new supply ducts and a gas line extension for a matching furnace is $150 + $75 + $75 = $300, before the separate electrical permit for the new circuit. No drawings are required for most of this work, so the fee is paid at issuance; an online application that must be reviewed may carry a $25 review fee. Starting in 2026 the table is indexed to CPI, with the first adjusted schedule effective the following January 1.
Who Files and What They Submit
Chicago does not license HVAC contractors as a trade, so the mechanical permit lists a licensed general contractor (Class A through E), and an HVAC subcontractor is listed only if it will schedule the inspections. An individual may act as general contractor on their own primary residence (no more than 6 units, no building over 3 stories) once per calendar year. The electrical side is different: any hardwired connection or new circuit needs a Chicago-licensed electrical contractor and its own permit, with no homeowner exception. Every mechanical application uploads an existing-condition photo and the energy and water efficiency compliance form; new AC or heat pumps add a load calculation, which any responsible person may prepare to ACCA Manual J, and a site plan; duct or gas changes add an HVAC drawing. Refrigerant work must be done by EPA Section 608 certified technicians, gas piping is tested under Chapter 4 of the 2021 International Fuel Gas Code, and new outdoor equipment may not exceed 55 dB(A) at 100 feet or 70 dB(A) at 10 feet. A first inspection must pass within 540 days.
How to Get a HVAC Permit in Chicago
Decide whether the swap is in kind
Same type, size and shape at a home up to 4 stories means no building permit. A new type, fuel, capacity or location means an express mechanical permit.
Prepare the uploads
Take an existing-condition photo, complete the energy and water efficiency compliance form, and add a Manual J load calculation and site plan for new AC or a duct or gas diagram for piping changes.
Apply in the Express Permit portal
Choose Mechanical (HVAC) Work, list the licensed general contractor or your Form 401, and list the HVAC subcontractor if it will schedule inspections.
Pay at issuance
$75 per equipment type, $150 for new AC equipment, $75 each for duct or gas extensions, plus any $25 review fee; file the electrical permit separately through a licensed electrical contractor.
Install and request inspection
Test gas piping, keep outdoor units within the noise limits, and request the inspection in the portal within 540 days.