What's Required in Milwaukee
- Gas- and oil-fueled furnaces and boilers need an HVAC permit even for a like-for-like replacement.
- New air conditioning, heat pumps and ductwork need an HVAC permit.
- Plan review is not required for equipment replacement, AC-only systems or duct alterations of $10,000 or less.
- Permit applications must list the manufacturer, capacity, efficiency rating, model and location of the equipment.
- HVAC businesses must register with the State of Wisconsin, and contractors need a City Home Improvement Contractor License.
- New wiring for HVAC equipment needs an electrical permit by a state-licensed electrical contractor.
- Air-conditioning condensers must sit in side or rear yards outside the required setbacks.
Do you need a permit to replace a furnace or AC in Milwaukee?
For a gas furnace or boiler, yes. Milwaukee's code exempts the replacement of mechanical appliances in one- and two-family homes only when the equipment is not fueled by gas or oil (MCO 200-24-1.5-f-4), so a gas furnace, gas boiler or oil burner swap needs an HVAC permit even when it is like-for-like. The Department of Neighborhood Services (DNS) checklist lists Furnace: Yes.
Electric equipment is less clear. The same code exemption covers non-gas appliances, and DNS's homeowner page lists replacing air conditioners among work that needs no permit. But the DNS checklist lists Air conditioner: Yes. A new central AC where there was none, a heat pump added to a furnace, or new ductwork is installation, not replacement, and needs a permit. For a straight condenser swap, call the Permit and Development Center at (414) 286-8210 before relying on the exemption. Window units need no permit.
How much is an HVAC permit in Milwaukee?
Mechanical permits are flat per item under MCO 200-33-23: $55 per heating unit up to 150,000 BTU input (plus $25 per extra 50,000 BTU), $60 per air conditioning unit up to 3 tons (plus $10 per extra ton), boilers $60 per unit up to 150,000 BTU, and ductwork at $2 per 100 sq ft of conditioned area with a $50 minimum. Each permit adds a $25 processing fee, and DNS adds its 1.6% training and technology surcharge.
- Like-for-like 80,000 BTU gas furnace: $55 + $0.88 + $25 = $80.88.
- New 4-ton central AC: $60 + $10 = $70, plus $1.12 and $25 = $96.12, and the AC circuit needs an electrical permit.
- New furnace, 3-ton AC and new ductwork in a 2,000 sq ft house: $55 + $60 + $50 = $165, plus $2.64 and $25 = $192.64; electrical for the AC outlet and furnace at the $100 minimum, plus $1.60 and $25 = $126.60. Total $319.24.
Plan review is not needed for equipment replacement only, air-conditioning-only systems, or duct alterations costing $10,000 or less; for those jobs DNS still requires the permit itself.
| What you are doing | City filing | Rule |
|---|---|---|
| Replacing a gas furnace or boiler | HVAC permit, $55 or $60 per unit | Gas and oil equipment not exempt |
| Replacing an electric AC condenser in kind | Confirm with DNS | Code exempts non-gas appliances; checklist says AC: Yes |
| Installing new central AC or a heat pump | HVAC permit, $60 up to 3 tons | Plus electrical permit for the circuit |
| New or altered ductwork | HVAC permit, $2/100 sq ft, $50 min | No plans if the job is $10,000 or less |
| Window air conditioner | No permit | DNS homeowner list |
| Condenser placement | Side or rear yard outside setbacks | MCO 295-505-3-L |
| Outdoor wood-burning furnace | Prohibited | All residential districts |
Who can pull an HVAC permit in Milwaukee?
Apply on the Development Center alterations permit form, listing the manufacturer, capacity in BTU/hr or tons, efficiency rating (AFUE or SEER), model and location. Wisconsin requires any business that installs or services HVAC equipment to register with the state (Wis. Stat. 101.178), and the city requires a Home Improvement Contractor License of contractors doing heating and cooling work at one- and two-family homes. DNS lets owners who live in the home pull permits for their own work. Any new wiring for the equipment must be done by a licensed electrical contractor.
How to Get a HVAC Permit in Milwaukee
Check the fuel and scope
Gas or oil equipment, new systems and ductwork need a permit; ask DNS about a straight electric condenser swap.
Choose a registered contractor
Hire an HVAC business registered with the state and holding a City Home Improvement Contractor License, or pull the permit as an owner-occupant.
Gather equipment data
Collect the manufacturer, BTU/hr or tonnage, AFUE or SEER rating, model numbers and installation location.
Apply and pay
File the Development Center alterations permit form or apply through the Land Management System; pay the per-unit fee, surcharge and $25 processing.
Inspect
Have the installation inspected, plus the electrical permit inspection if a new circuit was run; start within 180 days of issue.