Permit Required? Required
Typical Fee Range $100–$300 Standard residential flat fee for system replacement.
Fee Method Flat fee
Apply Online Apply at Buildings, Safety Engineering, and Environmental Department →

What's Required in Detroit

  • Mechanical permit required for all HVAC unit replacements.
  • Manual J load calculations required for new system sizing.
  • Electrical permit mandatory for power connections to the unit.
  • Proper venting and condensate drainage must be installed.
  • Exterior unit must meet property line setbacks and noise codes.
  • Gas piping permit required if switching from electric to gas heat.

How to Get a HVAC Permit in Detroit

1

Step 1: System Sizing

Perform load calculations to select the correct unit size.

2

Step 2: Apply Online

Contractors file for mechanical and electrical sub-permits.

3

Step 3: Installation

Replace the furnace/condenser according to mechanical code.

4

Step 4: Safety Check

Ensure all gas and electrical connections are secure.

5

Step 5: Final Inspection

Inspector checks drain lines, safety switches, and performance.

Frequently Asked Questions

Yes, any permanent HVAC installation requires a permit.
Minor component repairs generally do not require a mechanical permit.
Refrigerant work requires a state-licensed technician for safety.