Resources

Electrical Calculators, Guides & Resources

Free tools and plain-English guides written by our electricians, so you can plan the job before you call. And when you do call, there’s no trip charge for the quote.

Size a panel for an EV charger, lay out recessed lights, pick the right light color for the whole house, size a ceiling fan, or find out whether your project needs a permit. Everything here uses the same rules we use on the job, and nothing you type is uploaded or saved.

Open the calculatorsBrowse the guides(919) 888-3500

4.9 ★ · 620+ reviews · NC License #29565 · 5-year workmanship warranty · Free in-home quotes

4Free interactive toolsBuilt on the NEC and our own job rules
4.9 ★Average rating620+ reviews on Google
Since 2011Serving the TriangleLicensed, insured, NC License #29565
$0To use any of themNothing uploaded, nothing saved, no sign-up
Interactive tools

Plan it before you call

Four calculators our electricians built from the rules they actually use. Each one gets you to a number or a layout; the free in-home quote is where it becomes a price.

Panels & EV

Electrical Load Calculator

A quick homeowner check or the full NEC 220 worksheet, your choice. Add an EV charger, hot tub, tankless water heater or pool and see whether your panel has the capacity, in VA, with the NEC minimum and our recommended headroom shown separately.

Open the load calculator →
Lighting

Recessed Lighting Planner

Pick the room, enter its size and get a layout and a light count using the same spacing rules our electricians use on the job: corners, counter runs, islands, bedrooms, and where a fan or chandelier sits.

Plan my recessed lights →
Lighting

Light Color Guide

The Kelvin slider that shows what 2700K, 3000K and 4000K look like, “paint your own room” to tint a photo of your space, and “decode the box”: type in a bulb’s Kelvin, CRI and lumens and find out if it matches the rest of your house.

Open the light color guide →
Fans

Ceiling Fan Size Calculator

Room type, size and ceiling height in; blade span, downrod length and damp or wet rating out, with a Lamps Plus search already filtered to fans that fit. Send us the model number and we install it.

Size my ceiling fan →

On a phone? The planner and the light color guide work best turned sideways. The light color guide can also read a bulb box with your camera; check what it fills in before you trust it.

Guides

Guides by topic

Each service page doubles as a guide: what the work involves, what we recommend and why, what it depends on, and the questions customers ask us most. Start with the one closest to your project.

Lighting

Lighting guides

Power & safety

Panels, power and safety

Commercial

Commercial and compliance

Working with ARC

Before you hire us

How these are written

By the electricians who do the work

Every guide and calculator on this page is written or checked by the electricians who do the work, not a marketing company. When we cite a number, it comes from the National Electrical Code, the manufacturer’s spec sheet or our own installs; where sources disagree, we say so. If you find something wrong, tell us and we’ll fix it.

  • Our recommendations are opinions, formed on thousands of Triangle homes. We tell you what we’d do in our own house.
  • Code references are to the NEC as adopted in North Carolina. Your town’s inspector has the final say on any job.
  • Nothing here replaces a visit. A calculator can’t see your panel; a licensed electrician can, and the quote is free.
Covered by the ARC Promise

When you’re ready to go from a plan to a price

A licensed electrician comes to the house, walks the job with you and puts the price in writing before any work starts. No trip charge, no estimate fee and no commission, so the recommendation is the one we’d make for ourselves.

Read the ARC Promise
Also from Allied Repair Company

Plumbing resources from ARC Plumbing

Our sister company keeps the same kind of library for plumbing: calculators, permits and plain-English guides written by the plumbers who do the work. Their resources page links back here for anything electrical.

Tool

Water heater finder

A few questions about the house; a tank, tankless or Essency recommendation with a planning price range.

On arcplumbing.com →Tool

Gas line BTU calculator

Totals the appliance BTUs and checks the load against a 3/4-inch line.

On arcplumbing.com →Guide

What’s that noise? What’s that smell?

Common plumbing sounds and odors, what you can check, and which ones are urgent.

On arcplumbing.com →Guide

How long does plumbing last?

Typical lifespans for water heaters, pipes, drains, fixtures and gas lines.

On arcplumbing.com →Permits

Plumbing permits by town

Permit offices, what needs one, and North Carolina’s water heater exemption.

On arcplumbing.com →Save money

Water heater rebates & credits

Utility and state programs compared, with eligibility and sources.

On arcplumbing.com →

See all plumbing resources on arcplumbing.com →

Coming next

Good questions tend to become pages

Most of what’s on this page started as a question a customer asked on a job. These are the ones we’re writing up now. If you need one of them sooner, call and ask; the electrician on the phone has the answer, the page just hasn’t been written yet.

  • Duke Energy and North Carolina rebates and tax credits for EV chargers, heat pump water heaters and panel upgrades.
  • The electrical checklist for buying or selling a home in Wake County: what inspectors flag, what to fix before listing.
  • What’s that buzz, flicker or burning smell? Electrical symptoms, what you can check, and which ones mean call now.
  • The NEC in North Carolina: which code year is in force and the state amendments that change it.
Questions

Resource questions

Are the calculators free, and do I have to use them before I call?

Yes, and no. They’re free, nothing is uploaded or saved, and nobody will call you because you used one. They exist so you can plan the job and ask better questions. If you’d rather skip straight to a visit, call or use the form below; the quote is free either way.

How accurate is the load calculator?

It follows NEC Article 220, the same method an electrician or inspector uses, and shows the NEC minimum next to the headroom we recommend. It can’t see the condition of your panel, the service wire or the meter base, so treat the result as the answer to “is this even close?” and let the in-home visit settle the rest.

Will the recessed lighting planner tell me the price?

It gives you a layout and a light count using the spacing rules we use on the job. Recessed lighting is priced per light, and the exact number depends on attic access, ceiling type and what’s already in the ceiling, so the price comes with the free in-home quote.

Is there a resource you’d like that isn’t here?

Tell us. Most of these pages started as a question a customer asked on a job. Email [email protected] and we’ll add it to the list.