Electrical Panel Installation
New construction, home additions, and detached structures — code-compliant service panel installations for Bonney Lake and Pierce County.
When Does a Home Need a New Panel Installation?
A new panel installation — as opposed to a replacement — is required any time a property needs electrical service where none currently exists, or where the existing service is being substantially expanded.
Custom homes, spec builds, and new residential construction in Pierce County all require a professionally designed and installed service panel.
Adding a mother-in-law suite, second story, or major room addition often requires a new subpanel or upgraded main service panel.
Workshops, detached garages, ADUs, and barns need their own subpanel fed from the main service — with proper feeder sizing and grounding.
Washington Code Requirements for New Installations
New panel installations in Washington must comply with the 2023 NEC and Washington Cities Electrical Code (WCEC) with state amendments. Here's what the code requires.
Panel Capacity & Type
- Washington requires a minimum of 100-amp service — most new homes install 200A or higher
- Panel must include a main disconnect and be listed as "suitable for use as service equipment"
- Must have adequate breaker spaces for current and future circuits
- Compatible with GFCI/AFCI breakers and surge protective devices
Location & Clearances
- Minimum 3 ft deep × 30 in wide clear working space
- Top of panel cannot exceed 6 ft 7 in above the floor
- Dedicated lighting source at the panel location
- Prohibited locations: bathrooms, clothes closets, damp spaces, above kitchen countertops
- Outdoor panels must be rain-tight and protected from mechanical damage
Safety Devices
- Surge protection — Type 1 or Type 2 SPD required on all new services (NEC §230.67)
- Emergency disconnect — Outdoor, within 50 ft, readily accessible (NEC §230.85)
- GFCI — Kitchens, baths, garages, laundry, basements, all exteriors
- AFCI — All 120V, 15- and 20-amp circuits in bedrooms, living rooms, kitchens, hallways, closets, laundry
- Tamper-resistant receptacles — Required in all habitable areas
Meter Base & Service Entrance
- Meter base installed concurrently with the panel
- Mast: 2-inch rigid steel conduit with weatherhead 18 in above the roof surface
- Meter center: 4–6 ft above grade, properly strapped
- Service entrance conductors sized to match panel rating
Load Calculations: Getting the Right Size
Undersizing a panel is one of the most common — and costly — mistakes in new installations. A proper load calculation per NEC Article 220 ensures your service handles today's demand and tomorrow's additions.
What Goes Into a Load Calculation
- Square footage of the home (general lighting & receptacle load)
- Kitchen small appliance circuits (minimum 2 × 20A)
- Laundry circuit (minimum 1 × 20A)
- HVAC system — furnace, heat pump, or central AC
- Water heater (tankless units draw 30–50A)
- Dryer, range/oven, and other fixed appliances
- EV charger (typically 40–50A)
- Hot tub, sauna, or pool equipment
- Solar PV or battery storage systems
for new homes
new construction
high-demand loads
multi-system homes
Dedicated Circuits: What Every New Panel Needs
Code and best practice require dedicated circuits for specific appliances. Overloading multi-wire branch circuits causes nuisance tripping, overheating, and potential fire hazards.
| Circuit | Typical Rating | Protection Type |
|---|---|---|
| General lighting & receptacles | 15A or 20A (120V) | AFCI in habitable rooms |
| Kitchen small appliances (×2 min) | 20A (120V) | GFCI required |
| Bathroom receptacles | 20A (120V) | GFCI required |
| Laundry | 20A (120V) | GFCI required |
| Refrigerator | 20A (120V) | Dedicated |
| Dishwasher | 20A (120V) | GFCI required |
| Microwave | 20A (120V) | Dedicated |
| Electric range / oven | 40–50A (240V) | Dedicated |
| Electric dryer | 30A (240V) | Dedicated |
| HVAC system | Per equipment specs | Dedicated |
| Water heater (tankless) | 30–50A (240V) | Dedicated |
| EV charger (Level 2) | 40–50A (240V) | Required by code |
| Garage receptacles | 20A (120V) | GFCI required |
| Exterior receptacles | 20A (120V) | GFCI required |
Grounding & Bonding: The Foundation of a Safe Panel
Proper grounding protects your family from electrical shock and your home from fire. Every new installation must comply with NEC Article 250.
Ground Rods
Two ground rods installed 6–8 ft apart, driven to full depth. The grounding electrode conductor connects the panel to the rod system.
Water Pipe Bond
The grounding electrode conductor must connect to the metal water piping within 5 ft of its point of entry into the building.
Gas Pipe & Metal Systems
Metal gas piping and other conductive systems (ductwork, structural steel) must be bonded to the grounding system to prevent shock hazards.
The Panel Installation Process
From design to final inspection — here's what a professional new panel installation looks like with CBR Electric.
Design & Load Calculation
A licensed electrician designs the service based on NEC Article 220, accounting for square footage, planned appliances, EV chargers, heat pumps, solar systems, and future expansion. We select the correct panel size, type, and location.
Permits & Utility Application
We obtain the electrical permit from Washington L&I (or the local jurisdiction) and apply to the utility — Tacoma Power or PSE — for new service. This includes meter base specs, transformer requirements, and connection scheduling.
Service Entrance Installation
Install the meter base, service mast (2-inch rigid steel conduit with weatherhead 18 in above the roof), and service entrance conductors. The meter center is positioned 4–6 ft above grade and properly strapped.
Panel Mounting & Safety Devices
Mount the panel in the designated location with required clearances. Install the main disconnect, Type 1 or Type 2 surge protective device, and outdoor emergency disconnect. Verify proper height, labeling, and lighting.
Grounding, Bonding & Branch Circuits
Install the grounding electrode system (two ground rods, water pipe bond, gas pipe bond). Wire all branch circuits with appropriate gauge conductors, install GFCI/AFCI breakers where required, and label every circuit clearly.
Testing & Inspection
Test all breakers and circuits, verify that AFCI and GFCI devices trip correctly, and confirm proper voltage at each outlet. Schedule a final inspection with L&I or the local jurisdiction. The utility connects service only after the inspection passes.
Main-Breaker vs. Main-Lug Panels
Understanding the difference is important — using the wrong type in the wrong application is a code violation and a safety hazard.
Main-Breaker Panel
- Includes a built-in main disconnect
- Used as service equipment — the primary panel for the home
- Provides overcurrent protection at the service entrance
- Required for all new residential service installations
Main-Lug Panel
- No built-in main breaker — lugs only
- Used as a subpanel fed from the main panel
- Relies on the breaker in the main panel for overcurrent protection
- Not suitable for service disconnect unless upstream protection is provided
Planning for Solar, Batteries & Backup Generators
If solar PV, battery storage, or a backup generator is in your plans — even years down the road — it's critical to account for them during panel installation.
Solar PV & Battery Storage
- NEC 705.12 requires the sum of the main breaker and solar back-feed breaker not to exceed 120% of the bus-bar rating
- A 200A panel with a 200A bus bar allows a maximum 40A solar back-feed breaker
- Larger solar arrays may require a panel with a higher bus-bar rating or a dedicated solar panel
- Battery storage systems need dedicated circuits and proper disconnects
Backup Generators
- Generators require a transfer switch to prevent back-feeding the utility grid
- Manual transfer switches are the most common for residential standby power
- Automatic transfer switches (ATS) are used for whole-home standby generators
- Panel must accommodate the transfer switch and generator circuit breaker
Installation Considerations for Washington's Climate
The Pacific Northwest's moisture, temperature swings, and storm exposure create specific challenges for electrical installations that need to be addressed from day one.
Moisture Protection
Outdoor panels must be NEMA 3R rated (rain-tight). Indoor panels in garages and basements need extra attention to condensation and water intrusion. Proper weatherheads and service entrance sealing prevent moisture migration.
Surge Protection
Washington's storm season makes whole-home surge protection essential — not just code-required. An SPD protects HVAC, electronics, and appliances from utility-side surges and lightning strikes.
Tree & Storm Exposure
Overhead service in wooded areas is vulnerable to falling branches and wind damage. Consider the service entrance location, mast height, and whether underground service is a better long-term option for your property.
Common Panel Installation Mistakes
These errors are found in both DIY work and unlicensed contractor installations. Every one of them creates a safety hazard or a code violation — and all of them are preventable.
Installing 100A when the load calculation calls for 200A. Leads to overloaded circuits, nuisance tripping, and an expensive upgrade shortly after construction.
NEC §230.85 requires an outdoor emergency disconnect on all 1- and 2-family dwellings. Forgetting this fails inspection every time.
Neutral and ground must be separated in subpanels. Bonding them creates parallel current paths that can energize enclosures and cause shock.
Unpermitted work violates Washington law, voids insurance, and can delay or kill a home sale. All new panel installations require a permit and inspection.
14 AWG → 15A max, 12 AWG → 20A max. Oversizing a breaker without upgrading the wire is a fire hazard.
NEC §230.67 requires an SPD on all new services. This isn't optional, and inspectors are checking for it.
Common Questions About Panel Installation
How many circuits does a new home need?
At minimum, you'll need circuits for general lighting and receptacles, kitchen small appliances (2 minimum), laundry, bathrooms, HVAC, water heater, and dedicated appliances (range, dryer, dishwasher, microwave). The 2023 code also requires an EV-ready circuit. Plan extra breaker spaces for future additions — a full panel on move-in day is a design mistake.
Do I need a permit for a new panel installation?
Yes. All new electrical panel installations in Washington require a permit and inspection. In Bonney Lake, L&I handles most electrical permits. Some projects also require a building permit if structural work is involved.
Can I install a panel outside?
Yes, but the panel must be rated for outdoor use (NEMA 3R minimum), placed in a rain-tight enclosure, and protected from mechanical damage. It must still meet all clearance and height requirements and include an emergency disconnect.
What's the difference between a main-breaker and main-lug panel?
A main-breaker panel includes a built-in main disconnect and is used as service equipment — it's the primary panel for your home. A main-lug panel has no main breaker and is used as a subpanel, relying on a breaker in the main panel for overcurrent protection. Main-lug panels are not suitable for service disconnect unless upstream protection is provided.
How do I plan for solar if I'm not installing it yet?
Ask your electrician to install a panel with a bus-bar rating that accommodates the 120% rule (NEC 705.12). For example, a 225A bus bar on a 200A service gives you room for a 70A solar back-feed breaker. Also reserve a breaker position near the bottom of the panel for the future solar connection.
Is surge protection required on new installations?
Yes. NEC §230.67 requires a Type 1 or Type 2 surge protective device on all new services supplying dwelling units. The SPD must be integral to, or immediately adjacent to, the service equipment.
How long does a new panel installation take?
For new construction, the panel is typically installed during the rough-in electrical phase and finalized after drywall. The panel work itself takes 1–2 days. Permits, utility applications, and scheduling can add 2–4 weeks to the overall timeline.
See Related Services
Electrical Panel Replacement
Upgrade outdated or unsafe panels — FPE, Zinsco, fuse boxes, and undersized 100A service.
Circuit Breaker Replacement
Single breaker swaps, GFCI/AFCI upgrades, and troubleshooting tripping breakers.
EV Charger Installation
Dedicated 240V circuits and Level 2 charging — a natural add-on during panel installation.
Building or Adding On? Get the Panel Right.
CBR Electric designs, permits, and installs service panels for new construction, additions, and detached structures across Pierce County and King County.
📞 Call (253) 442-9930 Or email cbrelectric44@gmail.com · Bonney Lake, WA
