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Subpanel Installation in San Jose, CA
Dedicated subpanel installation for ADUs, garages, workshops, and high-demand circuits. Licensed electricians, no subcontractors. Workmanship warranty on every subpanel installation we complete.
Serving Santa Clara & San Mateo Counties
The Right Electrical Solution for Your Property
A subpanel draws power from your existing main panel and routes it to a specific area of your property. It does not replace your main panel. It extends available capacity to where you actually need it, without a full service upgrade.
Ozone Service handles the complete scope: load calculation, permit acquisition, feeder routing, installation, and city inspection. One licensed team, one contract, one warranty.
Common reasons Bay Area homeowners add a subpanel:
- Building or finishing an ADU, garage apartment, or backyard cottage
- Setting up a workshop with high-draw tools – compressors, welders, table saws
- Installing a Level 2 EV charger in a detached garage or driveway
- The main panel has sufficient amperage but has run out of available breaker slots
- Adding a hot tub, pool equipment, or irrigation system requiring a separate disconnect
- Room addition or remodel requiring circuits routed from a closer distribution point
What's Included in EverySubpanel Installation
As standard scope – not billable add-ons – every installation we complete includes the following:
Load Calculation
We calculate the actual amperage demand for the circuits being added before recommending a panel size. A 60A subpanel on a project that needs 100A creates problems within a few years. We size it for what the space will realistically require – today and down the road.
Feeder Wire and Conduit Routing
We run the feeder cable from your main panel to the subpanel location – through walls, attic space, crawl space, or underground conduit depending on the route. All wiring meets current NEC and California Electrical Code requirements. No exposed conductors, no shortcuts on conduit fill ratings.
Panel Installation and Circuit Wiring
We mount the subpanel enclosure, land the feeder, install breakers, and wire every circuit specific to your project. Each circuit is labeled, documented, and tested before we leave.
Grounding and Bonding – Done Correctly
A subpanel requires a separate ground and a floating neutral bus, unlike a main panel where ground and neutral share a bar. Incorrect bonding at a subpanel is among the most common code violations found at inspection. We wire it right the first time.
Permits and City Inspection
The California Electrical Code requires a permit and final inspection for every new subpanel installation. We pull all required permits through the City of San Jose or the relevant jurisdiction before work begins. No permit means no legal protection and no warranty enforcement. We don’t skip this step.
Dedicated Circuits as Part of a Larger Incentive Project
A standalone dedicated circuit typically does not qualify for rebates on its own. When the circuit is installed as part of a qualifying project – EV charger, heat pump, or heat pump water heater – the electrical work is often included in the rebate calculation under Bay Area incentive programs.
Local utility programs can be stacked with state programs. We check what applies to your specific project at the free estimate and handle all documentation.
Sample Сalculation
San Jose homeowner, heat pump installation, standard income:
SVCE
$2,500
CA Energy-Smart Homes
$5,750
Net savings
$8,250
Rebate availability changes quickly and is often first-come, first-served or waitlisted. We calculate your exact eligibility and current stacking options as part of the free estimate – no guesswork, no surprises.
This Project May Cost Less Than You Think
When a subpanel installation supports a qualifying upgrade – heat pump, heat pump water heater, or EV charger – Bay Area incentive programs may offset a significant portion of the cost. Local utility programs can be stacked with state energy incentives, reducing out-of-pocket expenses on the electrical scope.
We check which programs apply to your specific project at the free estimate and handle all documentation on your behalf.
From First Call to Final Inspection
Step 1
Free Estimate & Load Calculation
We visit your property, inspect the main panel, measure the feeder route, and calculate the exact amperage your project requires. You leave with a written scope and price. No charge, no obligation.
Step 2
Permit Application
We apply for the required electrical permit through the City of San Jose or the relevant jurisdiction before any work begins. In California, a subpanel installation without a permit carries no legal protection and no inspection sign-off. We never skip this step.
Step 3
Feeder Routing and Panel Installation
Our licensed electricians run the feeder cable, mount and wire the subpanel, install breakers, and complete grounding and bonding to code. Most residential subpanel jobs are finished in one day. Projects requiring underground conduit or significant wall penetration may require two.
Step 4
Commissioning and Handoff
We test each circuit, confirm breaker ratings, label the panel clearly, and walk you through what was installed. You receive a copy of the permit and a documented record of the completed work.
Step 5
City Inspection
We schedule and attend the inspection before the job is closed out. Our 100% inspection pass rate is the result of pulling permits, wiring to code, and not cutting corners on grounding, bonding, or documentation.
Why Bay Area Homeowners Choose Us for Subpanel Installation
HVAC and Electrical Under One License
Most subpanel installations are part of a larger project – heat pump install, EV charger, or ADU buildout. When two separate contractors handle electrical and HVAC, accountability gaps appear the moment something goes wrong. We carry both licenses. One team, one warranty, one point of contact.
100% Pass Rate
Every subpanel we install passes city inspection on the first attempt. That's the result of pulling permits every time, wiring to code, and getting grounding and bonding right. An inspector sees the work clearly. We make sure it's correct before they arrive.
No Subcontractors
When you book with Ozone, the crew that shows up is our crew – not labor sourced from a staffing platform. Our licensed electricians are direct employees. That matters for accountability, consistency, and warranty enforcement.
Authorized Dealer & Installer
Real Projects, Real Installations
Every photo shown here is from an actual Ozone Service subpanel installation – permitted, city-inspected, and under full warranty.
What Our Customers Say
Commercial Subpanel Installation
We install subpanels for commercial properties across the Bay Area – tenant improvements, office buildouts, retail spaces, multi-unit residential, and light industrial facilities. Commercial subpanel work follows the same process: load assessment, correct amperage specification, permit acquisition, licensed installation, and city inspection.
For projects requiring higher amperage configurations or general contractor coordination, contact us directly to discuss scope and timeline.
Frequently Asked Questions
What is the difference between adding a subpanel and upgrading my main panel?
A main panel upgrade replaces your service entrance – the point where utility power enters your home. A subpanel draws from your existing main panel and distributes power to a separate area of your property. If your main panel has sufficient amperage but has run out of circuit slots, or if you need power in a location far from the main panel, a subpanel is usually the correct and more cost-effective solution. We assess both during the free estimate and recommend the right path.
How large a subpanel do I need for an ADU?
It depends on the ADU’s projected electrical load. A studio ADU with a mini-split, basic kitchen, and lighting typically works well with a 60A panel. A larger ADU with a full kitchen, EV charger, and heat pump may require 100A or more. We calculate the actual load during the site assessment – not estimate by square footage.
Can I add a subpanel if my main panel is already full?
Yes, you can, provided your main panel has sufficient amperage remaining. A 200A main panel in a typical Bay Area home can generally support a 60–100A feeder to a subpanel without a full service upgrade. If your main panel is both out of circuit slots and near its amperage limit, we evaluate whether a standalone subpanel, a main panel upgrade, or a combination is the right approach.
How far can the subpanel be from the main panel?
There is no code-mandated maximum distance. However, longer feeder runs require larger wire to compensate for voltage drop, especially for high-draw loads like EV chargers. For runs over 100 feet, we specify the correct wire gauge during the estimate to ensure the circuits at the subpanel receive full voltage under load.
Do subpanel installations qualify for rebates or incentives?
A standalone subpanel installation typically does not qualify for rebates on its own. When the subpanel supports a qualifying installation – heat pump, heat pump water heater, or EV charger – the electrical work is often included in the rebate calculation under programs. Local utility programs may stack on top. We determine eligibility during the estimate.
Does subpanel installation require a permit in San Jose?
Yes, it does. Any new subpanel installation in San Jose and throughout Santa Clara and San Mateo counties requires an electrical permit and final inspection. We pull all permits and attend the inspection. Unpermitted subpanel work creates complications when you sell the property, voids most manufacturer warranties, and carries no legal protection if something fails later.
How long does a subpanel installation take?
Most residential subpanel installations are completed in one day. Projects that involve underground conduit runs, significant wall or ceiling penetration, or are part of a larger ADU buildout may require two days. We provide a specific timeline during the free estimate before any commitment.
Can the subpanel support an EV charger and future additions at the same time?
Yes, it can, if sized correctly from the start. When we calculate the load, we account for current requirements and a reasonable projection of what the space will need. Installing a 100A subpanel for a garage that currently only has an EV charger gives you capacity for a second charger, a heat pump mini-split, or additional workshop circuits later without touching the feeder again.
Get a Free Estimate for Subpanel Installation
No trip fee. No diagnostic charge. A licensed electrician assesses your property, calculates the load, and gives you a written scope and price before any work begins.
- go@serviceozone.com
- Serving Bay Area, 24/7
* and other cities in Santa Clara, San Mateo, and Alameda counties
