Upgrading Your Electrical Panel or Service? When You Need a Load Calculation
Why utilities and building departments ask for load calculations, what triggers them, and what the electrical package includes.
- When a load calculation is required
- What the electrical package includes
- Options before you upsize your service
- Serving All 50 States
- Sealed & Stamped
- Drawn In-House in CAD
- Quotes in 5-10 Min
When you add large loads – an EV charger, heat pump, ADU or kitchen remodel – or increase your service size, many utilities and building departments ask for a load calculation based on the National Electrical Code (NEC) showing the service can handle the total demand.
Why Do They Ask for a Load Calculation?
A load calculation adds up the electrical demand of the building using NEC Article 220 methods and compares it to the service rating. It proves the service, panel and conductors are adequate – or shows that an upgrade is needed.
What Usually Triggers One?
- Adding an EV charger or heat pump
- Building an ADU or large addition
- Electric range, dryer or water heater conversions
- Upgrading from a smaller service (for example 100A to 200A)
- Commercial tenant changes and new equipment
What Does the Electrical Package Include?
- NEC load calculation
- One-line (riser) diagram
- Panel schedule
- Service and feeder conductor and breaker sizing
- Grounding and bonding notes
Options Before You Upsize Your Service
A full service upgrade is not always needed. In some cases a load calculation shows the existing service is adequate, or load-management equipment recognised by the NEC can keep demand within the existing rating. We check these options first.
Working With Your Utility
Service changes often need utility approval and a scheduled disconnect. Your electrician coordinates this; our drawings and load calculation give the utility what it needs to review.
Want Us to Handle It for You?
We prepare the drawings, calculations and seal your permit needs – with a fixed price in 5-10 minutes.
What to Have Ready
- Address and utility provider
- Photo of the main panel and its label
- Existing service size
- List of new equipment (EV charger, heat pump, etc.)
- Square footage of the building
More Questions, Quick Answers
Do I always need a bigger service for an EV charger?
Not always. A load calculation may show your service is adequate, or load management can avoid an upgrade.
Can my electrician use your load calculation?
Yes. We prepare it for your electrician and the permit submittal.
Is the electrical package sealed?
Where your jurisdiction requires it, it is sealed by an engineer licensed in your state.
How much does a load calculation cost?
Send your panel photo and new equipment list for a fixed price in 5-10 minutes.
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Get Your Fixed Price in 5-10 Minutes
Tell us about your project and attach any plans or photos. An engineer replies with the scope, price and delivery date.
- Reply within 5-10 minutes on average
- Fixed price before any work begins
- Sealed by an engineer licensed in your state
- Your drawings stay confidential