McHenry County, IL Building Safety: Electrical Permits (2026)

McHenry County adopted the 2020 National Electrical Code with local amendments under Section 15.12.010, Ordinance O-202211-10-050. The county added its own enforcement article, 90.4, spelling out exactly when a permit is required. Subsection (A), Permits, states electrical wiring and equipment 'associated with an electrical service shall not be installed, replaced or otherwise modified without first submitting a permit application, securing approval and a permit through the McHenry County Planning & Development Department.'

Subsection (B), Exemptions, carves out several categories that skip the permit step: replacing lamps or plugging approved portable equipment into an already-approved permanent receptacle; radio and television transmitting-station equipment, though the power supply, towers and antennas for those stations still need a permit; temporary systems installed only to test or service other electrical equipment; and any work already listed as exempt under the adopted International Building Code, International Residential Code, or Article 90.2's scope section.

Subsection (C), Inspections, is what closes the loop: any permitted electrical work must be inspected by the building official, and the property owner or their agent is responsible for notifying the building official to schedule that Service Inspection once the work is done. Only after the building official confirms the installation complies with the code does the county issue written notification to the electric utility company authorizing it to energize the system, meaning the power company will not turn the service on without that sign-off. Rough-in inspections of concealed wiring must also happen before it's covered, before fixtures are set, and before the framing inspection.