Not Recommended. Requires licensed electricians, plumbers/gas fitters, and structural knowledge. Permit and inspection processes are complex and technical.
Installation involves significant electrical, fuel gas, and structural considerations, requiring specialized knowledge and adherence to multiple code disciplines. Permitting and inspections are comprehensive.
Project Guidelines & Rules
General Requirements & Permits
4 Rules
All whole-house generator installations require permits from your local municipality prior to commencement of work.
2024 IRC R105.1
All electrical and fuel gas work must be performed by appropriately licensed and insured contractors. Homeowner exemptions, if applicable, should be verified with your local building department.
2024 IRC R105.2, DuPage County Contractor Licensing Ordinances (as adopted by local municipality)
All installations are subject to mandatory inspections, including electrical, fuel gas, and final structural/site inspections, by your local building department prior to system operation.
2024 IRC R109.1
Installation must comply with all manufacturer's instructions, local noise ordinances, and property setback requirements.
2024 IRC M1307.1, Local Municipal Ordinances
Electrical Requirements (2023 NEC)
7 Rules
An approved transfer switch (automatic or manual) is required to isolate the premises wiring from the utility power source.
2023 NEC 700.5, 701.5, 702.5
The generator must be sized appropriately for the intended load, and load calculations must be provided.
2023 NEC Article 220 (Part III), 702.4(B)
Generator output must be connected to the transfer switch using approved wiring methods, properly protected by overcurrent devices.
2023 NEC Article 240, Article 300
The generator system, including the generator frame, must be properly grounded and bonded in accordance with NEC requirements.
2023 NEC Article 250
A readily accessible disconnecting means for the generator must be provided.
2023 NEC 445.18
All wiring and overcurrent protective devices must be suitable for the application and protected from physical damage.
2023 NEC Chapter 3, Article 240
Generators shall be clearly marked with rated power, voltage, and fuel type.
2023 NEC 445.16
Fuel Gas Requirements (2024 IRC, Illinois Plumbing Code)
6 Rules
Fuel gas piping (natural gas or LP) must comply with material, sizing, installation, and pressure testing requirements.
2024 IRC Chapter 24 (Fuel Gas), Illinois Plumbing Code (relevant sections)
Gas piping must be sized to provide adequate fuel supply at specified pressure for the generator and any other connected appliances.
2024 IRC G2413.4, G2413.5 (based on NFPA 54 sizing tables)
A sediment trap is required immediately upstream of the generator's gas control valve.
2024 IRC G2420.5.1 (NFPA 54, Section 5.9.6)
An approved manual gas shutoff valve must be installed upstream of the generator in a readily accessible location.
2024 IRC G2420.1.1 (NFPA 54, Section 5.9.1)
All gas piping must be properly supported and protected from physical damage and corrosion.
2024 IRC G2416.1, G2416.3
LP-gas containers and associated piping installations must conform to NFPA 58 (Storage and Handling of Liquefied Petroleum Gases).
2024 IRC G2401.1 (referencing NFPA 58), Illinois Plumbing Code (relevant sections)
Structural & Site Requirements (2024 IRC, DuPage County Climate)
6 Rules
The generator must be installed on a level, stable, non-combustible pad (e.g., concrete) designed to adequately support its weight and withstand weather conditions.
2024 IRC R301.1, R403.1
Minimum clearances from combustible materials, building openings (windows, doors, vents), and property lines must be maintained as per manufacturer's instructions, local fire code, and municipal ordinances (typically 5 feet from openings).
2024 IRC M1307.3.1, M1307.3.3, G2406.2
The generator and its pad must be securely anchored to resist wind uplift and potential seismic forces.
2024 IRC R301.2.1, R403.1.4
Any concrete pads or foundations supporting the generator, if separate from the main structure, must extend to the frost depth of 42 inches below grade.
2024 IRC R403.1.1, DuPage County Regional Standard
Adequate ventilation and access for maintenance and repair must be provided as per manufacturer's specifications.
2024 IRC M1305.1.4
Protection from vehicular impact may be required if the generator is located in an area susceptible to damage from vehicles.
2024 IRC R302.1 (implied for hazard protection)
Environmental & Safety
3 Rules
Generator exhaust must be directed away from all building openings and property lines to prevent recirculation of fumes into occupied spaces.
2024 IRC M1307.3.3
Noise emissions from the generator must comply with your local municipality's noise ordinances and nuisance regulations.
Local Municipal Ordinance
Consideration for fuel storage (e.g., LP tanks) must adhere to all local, state, and federal regulations for hazardous materials, including proper setbacks and containment.
2024 IRC G2401.1 (referencing NFPA 58 and 54)
