Sub-Panel Installation in West Palm Beach, FL
Out of breaker space? Adding a workshop, a pool, a garage apartment, or an EV charger? A sub-panel is often the cleanest way to add circuits without replacing your main panel. Nassif Electric has handled sub-panel installation across West Palm Beach since 1976. We're a Florida statewide licensed unlimited electrical contractor (License EC13001410), fully licensed, insured, and bonded. We calculate your available load, size the feeder correctly, pull the permit, and get the work inspected. Every job includes a free electrical safety inspection. Call 561-582-2600 for a free written estimate on your sub-panel installation.
What Is a Sub-Panel?
A sub-panel is a smaller breaker box fed from your main panel by a single circuit, called a feeder. It distributes power to a specific area, such as a garage, an addition, or pool equipment, and lets you add and switch off those circuits locally instead of walking back to the main panel.
Sub-Panel vs. Main Panel
| Main panel | Sub-panel |
Power source | The utility service (FPL) | A feeder breaker in the main panel |
Main disconnect | Shuts off the whole house | Shuts off only the circuits it feeds |
Neutral and ground | Bonded together at the service | Kept separate — the bonding screw is removed |
Grounding | Connected to the grounding electrode system | Ground runs back to the main panel; a detached building also needs its own ground rods |
Typical size | 150–400 amps | 30–125 amps (60 A and 100 A are most common) |
That neutral-and-ground separation is one of the most common mistakes in DIY sub-panel work. If the two are bonded in the sub-panel, current can travel on the ground wire, which is both a shock hazard and an inspection failure.
When You Should Add a Sub-Panel
- Your main panel is full. No open slots left, or the panel is packed with tandem breakers.
- Garage, workshop, or shed. A garage sub-panel powers tools, lighting, a compressor, and an EV charger from one place.
- Detached buildings. A guest house, ADU, studio, or pool house needs its own disconnect and panel.
- Pool and spa equipment. Pumps, heaters, and lights are easier to control and service on a dedicated sub-panel.
- Room additions and remodels. A kitchen or primary-suite remodel can add more circuits than the main panel can hold.
- Long distances. When an area is far from the main panel, one properly sized feeder to a sub-panel costs less than running many long individual circuits.
If your main service is already at its limit, adding a sub-panel alone won’t help. In that case we recommend a [200 amp panel upgrade] first, and the sub-panel after.
Our Sub-Panel Installation Services
Garage & Workshop Sub-Panels
A 60 or 100 amp sub-panel in the garage gives you dedicated circuits for tools, lighting, a freezer, and a Level 2 EV charger. See our [EV Charging Installation] page if a charger is part of the plan.
Detached Building Sub-Panels
For a detached garage, guest house, ADU, or workshop, we run an underground or overhead feeder, install the required disconnect and grounding electrodes at the building, and install the sub-panel.
Pool, Spa & Outdoor Sub-Panels
We install weather-rated sub-panels for pool and spa equipment, with the GFCI protection and equipotential bonding that Florida pool installations require.
Addition, Remodel & Tenant Sub-Panels
We add sub-panels for room additions, kitchen remodels, and separately metered or sub-fed spaces in commercial buildings and rental units. See our [Electrical Alteration and Renovation] page.
How Much Does Sub-Panel Installation Cost?
Most residential sub-panel jobs in West Palm Beach cost between about $900 and $2,500. Detached buildings that need trenching cost more. The feeder run is usually the biggest variable, not the panel itself.
Sub-panel job | Typical range* |
60 amp sub-panel, near the main panel (short feeder) | $900 – $1,600 |
100–125 amp sub-panel inside the home or attached garage | $1,200 – $2,500 |
Pool / spa equipment sub-panel (outdoor rated) | $1,200 – $3,000 |
Detached garage, ADU, or workshop (incl. trenching & disconnect) | $2,000 – $4,500+ |
Sub-panel added during a main panel upgrade | Reduced — some work overlaps |
What affects the cost to install a sub-panel:
- Sub-panel amperage and number of circuit spaces
- Feeder length, wire size, and whether it runs in conduit, underground, or through finished walls
- Trenching and restoration for detached buildings
- Whether your main panel has room for the feeder breaker (if it doesn’t, you may need a panel upgrade first)
- Indoor vs. outdoor, weather-rated equipment
- Permit and inspection fees for your city
What a Code-Compliant Sub-Panel Install Requires
A sub-panel looks simple, but a few details decide whether it passes inspection and stays safe:
- Load calculation first. We confirm your main service can actually support the new load before adding anything.
- Correctly sized feeder breaker and wire. The wire is sized for the breaker, the distance, and the conductor type, so the feeder doesn’t overheat or drop voltage.
- A 4-wire feeder: two hot conductors, a neutral, and a separate equipment ground.
- Neutral and ground kept separate in the sub-panel, with the bonding screw or strap removed and a separate ground bar installed.
- Working clearance: roughly 36 inches of clear space in front of the panel and about 30 inches of width, with nothing stored in the way.
- Detached buildings need a disconnecting means and their own grounding electrodes (ground rods) at the building.
- Torqued connections and clear labeling, then a permit and final inspection.
These are the details most DIY sub-panel installs miss, and they’re the ones an inspector checks first.
Our Process
- Free inspection & load calculation: We look at your main panel, available capacity, and the route for the feeder.
- Written estimate: Sub-panel size, feeder route, and scope, with no surprise charges.
- Permit: We pull the electrical permit for your city or Palm Beach County.
- Installation: We mount the sub-panel, run and terminate the feeder, separate the neutrals and grounds, and connect your circuits. Most installs take less than a day; detached buildings can take longer.
- Inspection & testing: We schedule the inspection, then test and label every circuit.
Why Choose Nassif Electric
- Since 1976: 50 years of residential, commercial, and industrial electrical work
- Florida statewide licensed unlimited electrical contractor: License EC13001410
- Licensed, insured & bonded
- Permits and inspections handled for you
- Free electrical safety inspection with every job
- 24/7 emergency response
Areas We Serve
We install sub-panels throughout West Palm Beach and South Florida, from Juno Beach to Fort Lauderdale, including Palm Beach, Palm Beach Gardens, North Palm Beach, Jupiter, Riviera Beach, Lake Worth Beach, Greenacres, Wellington, Royal Palm Beach, Boynton Beach, Delray Beach, and Boca Raton.
Frequently Asked Questions
Most sub-panel installations in the West Palm Beach area cost about $900 to $2,500. A short run near the main panel is at the low end; a detached garage or workshop that needs trenching usually runs $2,000 to $4,500 or more.
We don’t recommend it. The feeder connects to live bus bars in your main panel, the work requires a permit and inspection, and the most common mistakes (bonding neutral to ground, undersized feeder wire) are hazardous and fail inspection. A licensed electrician also protects your insurance coverage.
Often, yes. If there’s physical space for a feeder breaker and the load calculation allows it, a sub-panel is a good way to gain circuit space. If there’s no room or no spare capacity, we’d recommend upgrading the main panel first.
It depends on your calculated load, not just the service size. Many homes with 200 amp service can support a 60, 100, or even 125 amp sub-panel. We run a load calculation to confirm.
Yes, this is very common, as long as your main panel accepts a 100 amp feeder breaker and the load calculation supports it.
Technically a 100 amp feeder can be installed, but it doesn’t create more power. Everything still shares the same 100 amp service, so if you’re already near your limit, a service upgrade is the better solution.
It depends on the feeder’s amperage, the distance, and whether the wire is copper or aluminum. For example, a 100 amp feeder needs significantly larger wire than a 60 amp feeder, and longer runs need an upsize for voltage drop. We size it as part of the estimate.
Neutral and ground are bonded only once, at the main service. If they’re also bonded in the sub-panel, normal current can flow on the ground wire and on metal parts, which is a shock hazard and an inspection failure.
Yes. Adding a sub-panel requires an electrical permit and a final inspection. We handle both.
Most installs are finished in less than a day. Detached buildings that need trenching or long conduit runs may take a second day, plus inspection scheduling.
Schedule Your Sub-Panel Installation
Whether you’re powering a garage, a pool, an addition, or a guest house, Nassif Electric will size it right, install it to code, and get it permitted and inspected.
Call 561-582-2600 or email info@nassifelectric.com to book your free electrical safety inspection and get a written estimate.
