Home›Knowledge›NEC Article 220 — Branch-Circuit, Feeder, and Service Load Calculations
📋 Codecodeselectrical

NEC Article 220 — Branch-Circuit, Feeder, and Service Load Calculations

Updated Mar 26, 2026
Methods for calculating electrical loads to size conductors, panels, and service entrance.

NEC 2023 Article 220: 220.12 general lighting load by occupancy (Table 220.12): dwelling 3 VA/sf, office 3.5 VA/sf, retail 1.5 VA/sf. 220.14 receptacle loads: 180 VA per general receptacle outlet. 220.52 small appliance and laundry loads: 2 circuits at 1,500 VA each (small appliance), 1 circuit at 1,500 VA (laundry). 220.40 general method: sum all loads, apply demand factors (Table 220.42 lighting demand: first 3,000 VA at 100%, next 117,000 at 35%, remainder at 25%). 220.82 optional calculation for dwellings: 100% of first 10 kVA, 40% of remainder + largest motor. Example: 2,500 sf home = 7,500 VA (lighting) + 3,000 VA (small appliance) + 1,500 VA (laundry) + fixed appliances = total demand. Minimum 100A service for single-family dwelling.

TAGS
NECload-calculationservice-sizingdemand-factorpanel-sizing
DETAILS
code year
2023
code system
NEC
code section
Article 220
RELATED KNOWLEDGE
📋 Code
IBC 903.2.1 — Group A Occupancies (Sprinkler Requirements)
Automatic sprinkler system required throughout buildings with Group A occupancy where fire area exceeds 5,000 square feet, or overall building area exceeds 12,000 square feet, or occupant load of the fire area exceeds 300.
📋 Code
IBC 903.2.7 — Group M Occupancies (Retail Sprinkler Requirements)
Automatic sprinkler system required in Group M (mercantile) occupancies where fire area exceeds 12,000 square feet or building is more than three stories above grade.
📋 Code
IBC 903.2.11.3 — Buildings 55 Feet or More in Height
Automatic sprinkler system required throughout buildings with a floor level having an occupant load of 30 or more that is located 55 feet or more above the lowest level of fire department vehicle access.
📋 Code
IBC 1015.1 — Exit and Exit Access Doorways Required
Two exits or exit access doorways required from any space where occupant load exceeds the table values. Spaces with occupant load exceeding 500 require a minimum of 3 exits. Spaces exceeding 1,000 require 4 exits.
📋 Code
IBC 1017.2 — Exit Access Travel Distance
Maximum travel distance from any point in a building to an exit shall not exceed 200 feet unsprinklered or 250 feet sprinklered for most occupancies. Specific occupancies have modified limits.
📋 Code
IBC Table 601 — Fire-Resistance Rating Requirements
Specifies minimum fire-resistance ratings for structural elements based on construction type (Type I through V). Type IA requires 3-hour rated structural frame, 2-hour floors, and 1.5-hour roof.
← Back to Knowledge Garden