Subpanel installation in Santa Cruz County

Adding a subpanel for an ADU, garage, workshop, or detached structure. We size it, run the feeder, install the panel, and handle the permit.

CSLB #C10-109723720-year workmanship guarantee4.9 ★ on GooglePermit + inspection handled
02·What this is

A subpanel is a second, smaller breaker panel fed from your main panel — the standard way to bring real electrical capacity to a part of the property the main panel can't conveniently serve.

In Santa Cruz County the classic triggers are ADUs, detached garages turning into workshops or EV parking, and pool or spa equipment. Instead of running every circuit back to the main panel, a properly sized feeder carries power once, and the subpanel distributes it locally — cleaner runs, room for breakers, and capacity where the loads actually live.

The work: a load calculation to size the subpanel and feeder, the feeder run (through the building, or trenched conduit to a detached structure), the subpanel install itself — a Siemens panel by default, with breakers matching the panel brand for the UL listing — plus grounding at the structure where code requires it, and the AHJ permit and inspection.

One scope note: a subpanel adds distribution, not service capacity. If the load calc says your main service is already at its limit, the real fix is a 200-amp service upgrade — a full service rebuild, priced as its own project — with the subpanel sequenced after. The free inspection settles which situation you're in before anything is scheduled.

04·What's included

Exactly what we handle — and the two things you handle.

Sunrise provides

  • Load calculation to size the subpanel + feeder (usually 100A or 125A — the calc decides)
  • Feeder run from the main panel — interior routing or trenched conduit to detached structures
  • Siemens subpanel + breakers matching the panel brand (UL listing)
  • Grounding electrode at detached structures where code requires it
  • Permit + AHJ inspection
Warranty: 20-year workmanship, transferable · Permits: pulled + inspection coordinated by us, built into the quote · Cleanup: drop cloths down, debris hauled, panel labeled. Trench backfill and landscaping restoration are coordinated at quote — concrete and paver work is a separate trade

You provide

  • The plan for the space — what loads you expect now and later
  • Trench access decisions for detached runs (we coordinate digging scope at quote)
  • Panel + structure access on work day
05·How it works

Start to finish, with real times.

11–2 hrs on-site

Free home electrical inspection

A tech runs the load calc for the space, checks main-service headroom, scouts the feeder route, and sends a written quote. Detached runs get a trench-path walk while we're there.

22–3 week lead

Schedule

Install scheduled; for ADU projects we sequence with your builder's timeline so the subpanel is live when their trades need it.

3usually 1 day

Day of work

Feeder breaker lands in the main panel, feeder run pulled, subpanel mounted and terminated, circuits landed, everything labeled. Power to the rest of the house is down only briefly.

4short window

Inspection + handoff

AHJ inspection coordinated, panel schedule documented, paperwork left with you — useful for ADU occupancy sign-offs and insurance.

06·Pricing transparency

Every quote is free. The range depends too much on your home to fake it.

Quotes are free and specific. Subpanel cost is mostly the feeder — how far it runs and what it runs through. A garage on the other side of a slab is a different job than a wall-shared laundry room. The factors below are what actually move the number.

Financing · GoGreen Home
Financing is available through GoGreen Home when your project qualifies — typically when the subpanel supports a qualifying energy-efficiency upgrade (an EV charger in the garage, a heat pump, an induction range). We confirm your specific pathway at quote. No invented monthly figure — you see the real number once the scope is set.
Pre-qualify in 60 seconds — no credit impact
What it costs
Quotes are free.The variance on this work is too wide for an honest range — book a free inspection and we’ll give you a real number for your specific home, in writing.
What moves the number
Feeder length and routing (interior walls vs trenched conduit to a detached structure) · Trenching — existing conduit reusable vs new trench dug · Subpanel amperage per the load calc (100A vs 125A) · Whether the main service has headroom or needs an upgrade first · Grounding electrode work at detached structures · AHJ permit fees by jurisdiction
No hidden fees. Every quote is free and detailed.
08·What customers say · panel upgrades
4.9 on Google
146 reviews on Google
Read all reviews
Carlos and Aiden were prompt, polite, and an awesome duo. They knocked out a tough day replacing an ancient panel.
John R.
Subpanel replacement
We owned our own business for 25 years, and our experience with Sunrise Electrical was the best experience we have ever had! From the initial contact through the job completion, Branden and his team were fantastic. They are competent, efficient, effective communicators, care about their customers, and take pride in what they do. If you are looking for an Electrical Contractor you would be remis if you didn't give these folks a call.
Wayne B.
Panel upgrade
Thank you to the Sunrise Electrical Contracting team for updating the new main electrical system on my mom's home after the storm damaged the power lines and home equipment this winter… They replaced Main Service Upgrade Overhead, and added a Sub-Panel Install/Replacement Outdoors… the team of Branden, Jimmy, Ian, and Tylor worked long hours during the storm for a few days to get us up and running again before the next storm arrived.
Carrie
Storm-damage main service upgrade
09·Frequently asked questions

5 questions. Real answers.

Pulled from what we actually hear on quotes and on-site. If yours isn't here, ask us — we'll answer in plain English.

Do I need a separate PG&E meter for an ADU?
Sometimes yes, sometimes no. Many ADUs run happily on a subpanel from the main house service; some owners want separate metering for rental billing, and some jurisdictions or lenders push that way. Separate metering is a PG&E application with its own timeline and cost — we walk through both paths at the quote so you pick deliberately.
How big should the subpanel be?
The load calculation decides — usually 100A or 125A for ADUs and serious workshops. Going a size up on the subpanel is cheap at install time and expensive later, so when the calc is borderline we say so and size for what you told us is coming.
Does adding a subpanel mean upgrading my main panel too?
Only if the load calc says the main service is already at its limit. A subpanel redistributes capacity; it doesn't create it. When the service is the constraint, the right sequence is the 200A service upgrade first — and we'd rather show you that math at the quote than discover it at inspection.
Can you trench to my detached garage or ADU?
Yes — trenched conduit is the standard for detached runs. The cost swing is whether usable conduit already exists or a new trench has to be dug, and what surface it crosses (dirt beats concrete). We scope the path at the free inspection.
Is a permit required for a subpanel?
Yes — every Santa Cruz County AHJ treats a subpanel and feeder as permitted work with inspection. We pull the permit and coordinate; it's built into the quote.
10·Even if Sunrise isn't the answer

Here’s the honest path — wherever it leads.

We'd rather you get the right outcome than the Sunrise outcome. Some of this points away from us on purpose.

Outside Santa Cruz County?

Find a licensed CSLB C-10 electrical contractor, verify at cslb.ca.gov, and confirm the quote includes the load calc, the permit, and the inspection.

Browse our field guides

Is the main panel the real constraint?

A subpanel distributes capacity; it can't create it. The Panel Load Calculator runs the same NEC 220.82 math we use to tell which project you actually need.

Panel Load Calculator

Not sure what you need?

A free whole-home inspection tells you what's actually going on — you keep the written report either way. About a third of these end with no work scheduled, and that's fine.

Schedule a free inspection
12·Service areas

We do this work everywhere in Santa Cruz County.

From Davenport to Pajaro Dunes, San Lorenzo Valley to Pleasure Point. Same crew, same warranty, same pricing.

13·One more thing

Power where you actually need it?

Free on-site inspection, a real load calc, and a written quote. 20-year guarantee on the work.

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