Load check
Explore the electrical demand behind your project.
Compare illustrative household-demand and EV-charging scenarios. These simplified tools help organize project questions; they cannot confirm capacity, specify a safe circuit, or establish code compliance.
Tool 1 of 2
Residential load estimate
What your house asks of the service on paper, in the shape of the optional method for an existing dwelling. Tick what you own, slide the square footage, and watch the amps. This is an estimate for a conversation, not the load calculation a permit needs.
Heated square footage
outside dimensions, every heated floor
Kitchen counter circuits
code minimum is two
Laundry circuit
a 20 A circuit for the washer
Fixed appliances
typical nameplate VA; tick what is electric
Heating and cooling
the larger of heat or cool counts, at 100%
Nominal tons of cooling
EV charger
counted at 125% as a continuous load
Load estimate
105amps at 240 V
The smallest standard service with room for this is 150 A.
- 01General lighting, 3 VA per sq ft6,000 VA
- 02Counter and laundry circuits, 1,500 VA each4,500 VA
- 03Fixed appliances, nameplate25,400 VA
- 04First 10 kVA at 100%, remainder at 40%20,360 VA
- 05Heating or cooling, the larger, at 100%4,800 VA
- 06EV charger at 125%0 VA
- 07Total25,160 VA
Over 100 A on paper. A service change or a load-management device is the conversation.
A 150 A service has room for this.
A 200 A service has room for this.
An estimate, simplified from the NEC optional method. The permit calculation is done from your nameplates, and your local inspector (the AHJ) has the last word.
Tool 2 of 2
EV readiness check
The circuit a charger needs, whether it fits your service, and what the run costs. It uses the amps from the load estimate above, without the charger, so you are not counting it twice.
Existing service
the number on the main breaker
Charger you want
miles of range added per hour, roughly
Panel to parking spot
the wire run, not the walk
Two free spaces in the panel
a 2-pole breaker needs two, side by side
Use the load estimate above
105 A without a charger
Recommended circuit
60A breaker2-pole, 240 V
- 01Charger48 A at 240 V
- 02Wire6 AWG copper THHN in conduit; 4 AWG if it runs as NM cable
- 03Panel spaceA 2-pole breaker needs two adjacent free spaces. You have them, so no panel work beyond the breaker.
Fits the service
Your load estimate leaves about 95 A of headroom on 200 A. The charger adds 60 A on paper, so it fits.
Cost band
$1,100to$2,500
- Charger circuit, breaker, and wall unit connection$800 to $1,800
- Longer run and wire size$300 to $700
Bands are for planning; the charger unit is not included. Wire sizes assume copper and the terminal ratings on the equipment. The written estimate is what counts.
How the math works
Understand the calculation assumptions
A qualified electrician must determine the applicable calculation method and assess the actual equipment, installation, and local requirements. Do not use this demonstration result to select or install electrical equipment.
- General lighting and receptaclesHeated square footage times three. That is the code’s number for lights and general receptacles.3 VA / sq ft
- Kitchen counter and laundry circuitsTwo counter circuits minimum, plus one for the laundry.1,500 VA each
- Fixed appliancesRange, oven, dryer, water heater, dishwasher, and the rest, at the VA on the label. We use typical numbers here; the permit calculation uses yours.nameplate
- Demand factorThe first 10 kVA of all that at 100%, the rest at 40%, because not everything runs at once.100% / 40%
- Heating or coolingThey do not run together, so the bigger one counts. We take it at 100%, which is more conservative than the code allows for some heat.larger at 100%
- EV chargerA charger runs for hours, so it is a continuous load and counts at 125% of its amperage, outside the demand factor.125%
- AmpsTotal VA divided by 240 gives amps on the service. We call it room at 80% of the rating or below.÷ 240 V
Discuss your electrical project
Share the scope, your priorities, and the timing you have in mind. This inquiry form is part of the 3Fold Labs website demonstration.