Subpanel Installation in Rohnert Park, CA
Sized Right, for ADUs, Garages & More
An attached garage subpanel and a detached ADU subpanel are priced very differently — we'll tell you honestly which one applies, size it to what you're actually running, and handle the permit and grounding correctly the first time.
What Rohnert Park homeowners want to know first:
- Real pricing that changes based on where the subpanel is going — an attached garage subpanel and a detached ADU subpanel are priced very differently, and we'll tell you honestly which one applies.
- Building an ADU? We size the subpanel to what it'll actually run, not a generic number.
- Not sure if you need a subpanel or a full panel upgrade? We'll tell you honestly which one your home actually needs.
★★★★★
5.0 · 27 Google reviews
20+ years
in the trade
CSLB #1156335
licensed · bonded · insured
Sonoma County
owned & operated
Subpanel Installation
Why Rohnert Park Chooses Bright Right Electric
- Licensed under CSLB #1156335, with every subpanel sized to the loads you're actually planning.
- A family-owned crew that labels everything clearly, so you're never guessing later.
- Straightforward pricing you hear before we start, not after.
Subpanel Installation
What Is Subpanel Installation?
Subpanel installation adds a secondary electrical panel — commonly for a garage, workshop, ADU, or home addition — fed from your main panel, so that space gets its own dedicated circuits without maxing out the main. It's different from a full panel upgrade, which increases your overall main service capacity. Bright Right Electric installs subpanels for homeowners across Rohnert Park. This is one piece of our broader Panel Upgrades work. If you already know you just need general panel capacity rather than a subpanel specifically, see Circuit Breaker Installation, and if you manage a commercial property, see Subpanel Installation Commercial.
Subpanel Installation
Our Process
Every subpanel starts with the actual space and load it needs to serve.
01
Assess the space & load
We look at what the subpanel actually needs to power, now and reasonably down the road.
02
Written estimate
You get a real price in writing, sized to the actual amperage and location.
03
Permit filed
We file the required permit as standard.
04
Feeder run & grounding
For a detached structure, this includes the proper feeder wire and a dedicated grounding rod.
05
Subpanel installed & labeled
Every circuit gets labeled clearly, so it's never a mystery later.
06
Testing & documentation
The subpanel gets tested before we call it done, with a record of what was installed.
Subpanel Installation
How Much Does Subpanel Installation Cost?
It depends on the amperage and where the subpanel is going, and we'll tell you honestly which tier applies. A 50-60 amp subpanel in an attached garage commonly runs $400 to $900. A 100 amp subpanel on an interior wall or attached garage runs $700 to $2,200. A 100 amp subpanel in a detached garage with a trenched feeder runs $2,000 to $4,500. A 200 amp subpanel for an ADU or addition runs $1,800 to $4,500.
Those are honest general ranges, not a locked-in Bright Right Electric quote — the fastest way to get an exact number is to tell us what the subpanel needs to power and where it's going. Call (707) 791-5552 or request a quote below and we'll tell you plainly which tier your project falls into.
Subpanel Installation
Subpanel or Full Panel Upgrade — Which Do You Need?
A subpanel makes sense when your main panel already has room for one more feed breaker — it's the more affordable, more common path for a garage, workshop, ADU, or addition. A full panel upgrade is the better investment if your main panel is aged, undersized, or already at capacity with no room left for a new feed breaker at all. We'll tell you honestly which situation you're in rather than default to the bigger, more expensive job. See our Panel Upgrades page if a full upgrade turns out to be the right call.
Subpanel Installation
Building an ADU? Here's What You Need to Know
ADUs are one of the most common reasons we install subpanels across Sonoma County, and sizing it right matters. A 100 amp subpanel often suffices for a smaller ADU, while a full ADU with its own HVAC and kitchen commonly needs 125 to 200 amps. Because an ADU is a detached structure, it requires a proper 4-wire feeder — two hot wires, a neutral, and a separate ground — rather than an older 3-wire setup, plus its own grounding rod, which typically adds $200 to $500. If the feeder needs to run underground, trenching adds $8 to $14 per foot at a typical burial depth of 18 to 24 inches.
Subpanel Installation
Planning Other Electrical Work? Bundle and Save
If you already know you'll need an EV charger or a generator transfer switch alongside your subpanel, doing it all in one visit is worth considering. Bundling this work onto one permit is a real, practical way to save money and reduce how many separate visits your project requires — not a sales tactic.
Subpanel Installation
What's Included
Subpanel installation covers a few different scenarios. Here's what falls under it.
Attached Subpanel Installation
Adding a subpanel within the same building as your main panel, for a garage, basement, or addition.
Detached Subpanel Installation
Adding a subpanel in a separate structure — an ADU, workshop, or detached garage — fed from the main panel.
Feeder & Grounding for Detached Structures
The 4-wire feeder and dedicated grounding rod a detached structure's subpanel requires by code.
Circuit Breaker Installation
If you just need general panel capacity rather than a subpanel specifically, see Circuit Breaker Installation instead.
Panel Replacement & Service Entrance Upgrades
If your main panel itself needs attention rather than an additional subpanel, see Panel Replacement or Service Entrance Upgrades.
Commercial Subpanel Installation
For businesses, see Subpanel Installation Commercial for business-specific scope.
Subpanel Installation
Why Choose Bright Right Electric
Honest, tiered pricing.
We tell you plainly which cost tier your specific project falls into.
Real technical care.
Proper feeder wire, grounding, and clear labeling — every time, not just when it's convenient.
ADU experience.
We know how to size a subpanel to what an ADU actually needs to run.
Permit-first, every time.
Every subpanel gets filed and inspected properly.
08 ─────── Reviews
What Rohnert Park Customers Are Saying
"This is the most professional company I have ever worked with. I am a difficult person and hard to please (I have really high standards (as a retired science teacher) and I am skeptical of workmen and I'm a perfectionist!). Bright Right is currently working on the 3rd job I have hired them for – everything has gone smoothly, no stress at all!!! They are so friendly and so courteous. Rick and Dustin are an effective team with their two unique personalities – both very upbeat, serious, and kind. They explain everything in detail and answer all my questions (I am hyper-concerned about my property), and they are basically experienced, conscientious electricians you can trust."
— Nora Parker · Google Review
"I recently hired Dustin for some electrical work at my home, and I couldn't be happier with the results. He installed a high-quality bathroom fan, finished installing several outlets around the house, and completed a new electrical panel installation. From start to finish, Dustin was professional, knowledgeable, and clearly takes pride in doing the job right. The new panel installation was the bigger job, and Dustin handled it with real expertise. Everything was organized, labeled, and done to a very high standard, which gave me a lot of confidence in the safety and quality of the work."
— Google Review
"Bright Right did the electrical for our kitchen remodel and we couldn't be happier, we have since then added an EV with them and they were as good as the first time. Highly recommend!"
— Joey Evans · Google Review
"Shout out to Dustin Fildes, the electrician they sent to do the work at my house. You can tell he takes pride in his work. He's a very professional and very friendly. Individual would absolutely recommend Bright Right Electric and specifically Dustin to all my family and friends. Thank you Bright Right"
— Robert Horner, Google Review
Google Business Profile
5.0
Across 27 Google reviews
Subpanel Installation
Serving Rohnert Park and the Greater North Bay
Bright Right Electric provides commercial and tenant improvement electrical throughout Rohnert Park — offices, retail, and restaurants along the Commerce Boulevard and Redwood Drive corridors, and businesses near Sonoma State University and the University District — and out to Cotati, Penngrove, Petaluma, Santa Rosa, Sebastopol, Windsor, Healdsburg, Sonoma, and Cloverdale. Coverage extends into Marin County (San Rafael, Novato, Mill Valley, Sausalito, Larkspur, Corte Madera, San Anselmo, Fairfax, and Tiburon) and Napa County, including wineries, tasting rooms, and hospitality projects. If your property isn't listed, call anyway — the answer is usually yes.
Questions
Frequently Asked Questions
How much does subpanel installation cost?
It depends on amperage and location. A 50-60 amp subpanel in an attached garage runs $400 to $900, a 100 amp subpanel on an interior wall runs $700 to $2,200, a 100 amp subpanel in a detached garage with a trenched feeder runs $2,000 to $4,500, and a 200 amp subpanel for an ADU or addition runs $1,800 to $4,500. Call (707) 791-5552 for an exact number.
Do I need a subpanel or a full panel upgrade?
A subpanel makes sense when your main panel has room for one more feed breaker. A full panel upgrade is the better investment if your main panel is aged, undersized, or already at capacity.
What size subpanel do I need for an ADU?
It depends on the ADU's equipment — a 100 amp subpanel often suffices for a smaller unit, while a full ADU with its own HVAC and kitchen commonly needs 125 to 200 amps.
Does a detached garage subpanel need special wiring?
Yes. A detached structure requires a 4-wire feeder — two hots, a neutral, and a separate ground — rather than an older 3-wire setup, along with its own grounding rod.
How much does it cost to run a subpanel underground to a detached structure?
Trenching typically adds $8 to $14 per foot, with the feeder buried 18 to 24 inches deep.
How long does subpanel installation take?
A straightforward attached installation takes 4 to 8 hours. A detached structure installation with trenching can take 1 to 2 days or more depending on distance and site conditions.
Can I bundle a subpanel with other electrical work to save money?
Yes. Bundling a subpanel installation with an EV charger or a generator transfer switch on one permit can genuinely reduce total cost and disruption.
Do I need a permit for a subpanel installation?
Yes. Skipping the permit can void insurance coverage tied to the work and create a retroactive problem when selling the home.
What wire gauge does a subpanel need?
A 60 amp subpanel typically uses 6-gauge wire, a 100 amp subpanel uses 4-gauge or 2-gauge, and a 200 amp subpanel requires 2/0 or 4/0 wire.
Does a subpanel need its own grounding rod?
Subpanels installed in the same building as the main panel don't usually need one, but a subpanel in a separate detached structure typically does, adding $200 to $500. Call (707) 791-5552 if you're not sure which applies to your project.
Get in touch
Ready to Get Started?
Call (707) 791-5552 any time, day or night, or fill out the quote form below and we'll get back to you.
Phone
(707) 791-5552
(tap to call)
Address
1150 Holly Ave, Rohnert Park, CA 94928
Hours
7am - 5pm & 24 hour emergency services available.
15 ─────── Full service detail
Electrical Panel Upgrades in Rohnert Park
Replacing an undersized or obsolete panel is the most common job we perform in Rohnert Park, and it's the one that unlocks everything else. If your home still runs original 100-amp service, a Federal Pacific Stab-Lok, or a Zinsco panel, you're working with equipment engineered for a much smaller electrical load — and, in the case of those two brands, with a documented history of breakers that fail to trip. Upgrading to 200-amp service makes EV charging, battery backup, heat pumps, and modern appliance loads possible without constantly tripping breakers. We size the new service to what your household actually needs, pull the permit, coordinate the PG&E disconnect and reconnect, and meet the inspector for final sign-off.
EV Charger Installation in Sonoma County
Bright Right installs Level 2 home charging sized to your vehicle and, just as importantly, to your panel's actual available capacity. We run the dedicated 240-volt circuit, mount and commission the charger, and handle the permit — installing Tesla Wall Connectors, universal J1772 and NACS units, and hardwired or plug-in setups across Rohnert Park, Petaluma, and Santa Rosa. The detail most homeowners don't hear until it's too late is that many Sonoma County panels can't support a Level 2 charger without a service upgrade first, so we run a load calculation before you buy equipment, not after. We can also pre-wire a second circuit if a second EV is anywhere in your future.
Standby Generators & Backup Power
Public safety power shutoffs are a fact of life in Sonoma County, and so are winter storms that take lines down in the hills. We install whole-house standby generators with automatic transfer switches that pick up the house within seconds of an outage, wire inlets and manual transfer switches for portable generators, and add whole-house surge protection so your equipment isn't damaged when the utility comes back online. We'll also tell you honestly which tier makes sense — not every home in Cotati or Penngrove needs a whole-house unit when a critical-loads panel that keeps the refrigerator, well pump, internet, and a few circuits alive costs a fraction as much.
Solar & Battery Systems
We handle new photovoltaic installation, battery storage, system additions, and remove-and-replace work when a roof needs attention or a system has failed — plus service on existing arrays that aren't producing what they should. If you inherited a solar system with the house and nobody can tell you how it's wired or whether it's still under warranty, we can assess it and give you a clear picture. Battery storage in particular has changed the math for Sonoma County homeowners: between shifting utility rate structures under NEM 3.0 and the frequency of outages, a battery paired with existing solar is often a better investment than adding more panels.
Interior & Exterior Lighting
Recessed and can lighting, full LED retrofits, under-cabinet lighting, dimmer and smart-switch installation, fixture and chandelier hanging, landscape lighting, and security and motion-sensor lighting for homes across Rohnert Park and the University District. On the commercial side we handle lighting retrofits for offices, retail spaces, and warehouses along the Commerce Boulevard corridor, including the fixture and control changes that come with California Title 24 compliance. Lighting is one of the few electrical upgrades where the difference is immediately visible, and it's frequently the cheapest way to make a dated room feel finished.
Electrical Troubleshooting & Repair
Breakers that trip for no obvious reason, circuits that go dead, lights that flicker when the dryer starts, outlets that no longer hold a plug, GFCIs that won't reset, a faint burning smell you can't locate. These are the calls where experience shows. We trace a fault to its real source instead of swapping parts and billing for guesses, which is why our repairs hold and why we get called in behind other contractors who couldn't find the problem. In older Sonoma County homes the cause is often a failing backstab connection, a corroded neutral, a rodent-damaged run in a crawlspace, or a decades-old junction box buried behind drywall.
Custom Homes & New Construction
Full electrical for ground-up residential builds, major remodels, and additions throughout Sonoma, Marin, and Napa County — load calculations and plan review, service and meter setup, rough-in, trim, and final inspection. We work with general contractors, designers, and owner-builders, and we're comfortable on high-end custom projects near Sonoma State University where the lighting design, low-voltage layout, and smart controls all have to be coordinated before a single wire goes in. Getting the details right at rough-in is what keeps a home safe and functional for the next forty years — and it's far cheaper than fixing it after the drywall is up.
Commercial Electrical & Tenant Improvement
Service upgrades, panel and subpanel work, dedicated circuits for equipment, lighting retrofits, EV charging for employee and customer parking, and full tenant-improvement electrical for offices, retail, restaurants, and light industrial space along Redwood Drive and beyond. We understand a commercial job runs on someone else's schedule, so we work around business hours when the scope requires it. From a single dedicated circuit to a complete build-out, you get one licensed contractor coordinating permits, PG&E, and inspection — with clear pricing and a clean, code-compliant result.