TL;DR
A demand calculation is the NEC Article 220 arithmetic an electrician performs to determine whether a home's service and panel can absorb a new load, most often a 40-to-60-amp EV charger, without an upgrade. It totals square-footage lighting loads, appliance circuits, HVAC, and ranges, applying code demand factors that recognize not everything runs at once.
What it means
A demand calculation is the NEC Article 220 arithmetic an electrician performs to determine whether a home's service and panel can absorb a new load, most often a 40-to-60-amp EV charger, without an upgrade. It totals square-footage lighting loads, appliance circuits, HVAC, and ranges, applying code demand factors that recognize not everything runs at once. The result decides between a simple breaker addition, a load-management device that throttles the new equipment, or a service upgrade costing thousands, so the one-page calc sheet is worth requesting with the quote.
Where it sits in the glossary
Demand calculation is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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