Dwelling Load Calculator

Full NEC 220 residential load calculation with demand factors for permit applications

General Lighting & Receptacle Load (NEC 220.12 / 220.52)

Dwelling Square Footage

× 3 VA/sqft = 6,000 VA

Small Appliance Circuits (min 2)

× 1,500 VA = 3,000 VA

Laundry Circuit (1,500 VA)

HVAC (VA)

Water Heater (VA)

Dryer (VA)

Range / Oven (VA)

Dishwasher (VA)

Disposal (VA)

Custom Appliances

Recommended Service Size

150A

120/240V Single Phase

Total Connected Load

35,100 VA

Demand Load (after factors)

30,225 VA

Minimum Service (amps)

125.9A

NEC 220.42 Demand Factor Breakdown

General lighting + small app + laundry10,500 VA

First 3,000 VA @ 100%3,000 VA

3,001 – 120,000 VA @ 35%2,625 VA

General demand subtotal5,625 VA

Appliance loads (at 100%)24,600 VA

Total demand load30,225 VA

220.12General lighting load: 3 VA per square foot for dwelling units

220.52(A)Small appliance circuits: minimum 2 circuits × 1,500 VA each

220.52(B)Laundry circuit: 1,500 VA minimum (1 circuit required)

220.42Demand factors: first 3,000 VA @ 100%, 3,001–120,000 @ 35%, remainder @ 25%

230.79Minimum service: 100A for single-family dwelling