Demand factor for four or more fixed appliances

What the code requires

When calculating the load on a home's feeder or service with the standard method, the NEC allows a 75% demand factor on the combined nameplate ratings of four or more fastened-in-place appliances on the same feeder or service. Each appliance must be rated ¼ hp or more, or 500 W or more. This applies to one-family, two-family and multifamily dwellings.

Some appliances can never be part of this group: fastened-in-place cooking equipment, clothes dryers, space-heating equipment, air-conditioning equipment and, since 2023, electric vehicle supply equipment (EVSE).

On the job

• EV chargers are figured separately under 220.57, at 7,200 W (VA) or the nameplate rating, whichever is larger.
• Example: qualifying appliances totaling 8,400 VA count as 6,300 VA after the 75% factor.
• With fewer than four qualifying appliances, the factor does not apply and they are counted at full nameplate.
• The optional calculation in 220.82 handles fastened-in-place appliances differently, adding their nameplate ratings to the general loads instead of applying this 75% factor.

What changed in 2023

The 2023 NEC added electric vehicle supply equipment to the list of equipment that cannot use the 75% factor.

In California

For new construction, the 2025 CEC (625.1.1) also requires electric vehicle charging to comply with CALGreen, the California Green Building Standards Code.

Related sections

• NEC 220.57
• NEC 220.54: Electric clothes dryer load (5,000 VA minimum)
• NEC 220.55: Electric range and cooktop load calculations
• NEC 220.82: Optional load calculation for a single home

Where this comes from

• Leviton Captain Code 2023: 220.53 and 220.57
• Mark Earley, Electrical Contractor: More on 2023's Chapter 2 updates (Aug 15, 2022)
• LBNL: Low-power electrification, the NEC and building energy codes (Apr 18, 2024)
• Electrician U: Dwelling unit service load calculations, standard method (2023 NEC)
• Read the official NEC free at NFPA