Source panel & load assessment
Review the upstream panel, existing electrical demand and proposed equipment. Empty breaker spaces alone do not establish available capacity.
Subpanel Installation
Subpanels for Garages, ADUs & Home Additions
Bring circuits closer to the space you use. Start with available capacity, the feeder route and the equipment your project needs.
What & Why
More circuit space starts with a capacity check.
A subpanel is a second electrical panel supplied from an upstream panel through a feeder: the conductors carrying power between them. It can organize circuits in a garage, addition or accessory dwelling unit (ADU), or provide breaker spaces where the existing panel is full.
Adding a subpanel does not increase the utility service capacity. YKCA starts with the existing supply and proposed loads, then defines the feeder, panel location and circuits as one project.
What determines your subpanel scope
Power source
Existing panel condition and usable capacity
New loads
Equipment and circuits you want to add
Feeder route
Distance, access and finished surfaces
Panel location
Working access and indoor or outdoor use
Project concepts
Explore the installation possibilities
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Project Scope
The panel is one part of the installation.
The written scope connects the power source to the circuits you need.
Feeder & route planning
Confirm the route, length, access and surface repairs. Coordinate conductor selection and protection with the calculated load and installation conditions.
Panel & breaker compatibility
Choose equipment suitable for the location and confirm breaker and accessory compatibility with the specific panel listing.
Grounding & bonding
Coordinate the neutral and equipment grounding arrangement. A subpanel downstream of the service disconnect requires the appropriate separation; detached buildings need their own design review.
Permits & installation sequence
Identify local permit and inspection requirements, planned power interruptions and any work that must remain accessible before walls or trenches close.
Circuit identification & handoff
Include circuit labels, the agreed inspection records and an explanation of spare spaces versus the loads the feeder was designed to serve.
Decisions That Matter
Match the solution to the actual constraint.
Full panel, suitable supply
A subpanel may solve a lack of breaker spaces when the upstream system can support the added demand.
Garage or detached building
Route access, a building disconnect and grounding details can shape the work as much as the panel itself.
Future equipment
Identify likely additions now. Spare spaces are useful, but they do not reserve unlimited power for future appliances.
Before Your Consultation
Bring the equipment list and the destination.
You do not need to select a panel or feeder size before the assessment.
What you want to power
List the EV charger, tools, appliances, lighting or other equipment, including model information when available.
Where the work goes
Identify the proposed panel location, the area it will serve and any driveway, finished wall or landscaping along the route.
What already exists
Share available panel labels, prior permits and circuit schedules. Photos are a starting point; site verification establishes the final scope.
FAQ
Subpanel questions, answered.
Possibly. The decision depends on the existing service, upstream equipment and proposed demand. A subpanel can provide circuit spaces, but it does not increase the power available from the utility.
The feeder and protection are selected from the loads and installation conditions. The rating printed on a panel is not a promise of that much additional usable power. Define the equipment first, then establish the appropriate design.
That depends on the enclosure, feeder, equipment condition and working access. A replacement assessment should establish which existing parts can remain and which need to change.
The route to the separate building and its disconnect, grounding and bonding arrangements need review. Existing conduit or wiring is checked before it is treated as reusable.
A downstream subpanel uses an isolated neutral arrangement and a separate equipment grounding connection. The electrician confirms the correct configuration for the whole system and the selected equipment.
The route and access, feeder design, panel and breaker selection, circuit changes, permitting and surface repairs all affect the quote. A short visible distance can still involve difficult access or finished-wall work.
Only if the diagnosis shows the proposed redesign addresses the cause. A trip may involve a circuit load, equipment fault or wiring issue. Moving the circuit to another box is not a diagnosis.
The proposal should name them. Replacing a panel, installing a feeder and adding branch circuits are separate scope items that can be combined when your project needs them.
Planning references
These references explain capacity, equipment and installation principles. Final requirements are confirmed for your property and local jurisdiction.
Related project planning
Your Next Step
Plan the circuits your next project needs.
Tell us what you want to power and where. We’ll identify the questions to resolve before selecting the subpanel.
Contact Us
Request A Consultation
Local Services
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Or call us to discuss your project:
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