The NEC optional method for dwelling loads (NEC 220.82 in 2023, Article 120.82 in NEC 2026) provides a simplified alternative to the standard method that often yields a lower calculated demand for large homes. The optional method begins with the total connected load at 100% for the first 10 kVA (8 kVA under NEC 2026), then applies a 40% demand factor to the remainder. All loads except electric heating and air conditioning are lumped into a single general load figure. This approach is commonly used by engineers for new construction where a single calculation serves both the service sizing and load approval submissions.
NEC 220.82 optional method: General load = (2,500 sq ft × 3 VA) + (2 × 1,500) + 1,500 + 1,200 + 900 + 5,000 = 18,600 VA. First 10,000 VA at 100% = 10,000 VA; remaining 8,600 VA at 40% = 3,440 VA. Add AC at 100%: 8,000 VA. Total demand = 21,440 VA. Service = 21,440 / 240 = 89.3A. Use 100A service minimum.
This is a variant of the full Dwelling Load Calculator — which supports both the NEC standard and optional methods with all appliances, HVAC, and EV charger loads.
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