Electrical Service Sizing

Dwelling unit and multifamily building service calculations per NEC Article 220.
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Method

Optional calculation for a single dwelling unit. 120/240V, single-phase, 100A minimum service.

General Loads

Small appliance circuits: 1,500 VA each per §220.52(A). Laundry: 1,500 VA each per §220.52(B).

HVAC Load

Larger of heating or cooling is used — they are non-coincident per §220.60.

Appliances & Other Loads

ApplianceVA EachQty

EV Charging Load

Per §625.42 — continuous load, 125% already factored into nameplate VA. Common: Level 2 @ 7,680 VA (32A × 240V) or 9,600 VA (40A × 240V).

Multifamily Building — §220.84

§220.84 requires minimum 3 dwelling units. Unit load calculated above is applied per Table 220.45 demand factors.

Corridor lighting, elevator, fire pump, common laundry, mechanical — added at 100% to building total.

Results

Per 2020 NEC (as adopted by NJ UCC) Article 220, Tables 220.12, 220.42, 220.45, 220.54, 220.55, and Sections 220.52, 220.53, 220.60, 220.82, 220.83, 220.84, 430.24, 625.42. Verify all calculations against current adopted code edition. Service conductor sizing per Table 310.12 not included — verify with manufacturer ampacity tables. Green Stories LLC is a building design and consulting firm.