Detached Garage EV Charger Installation Guide (Henderson 2026)

Detached Garage EV Charger Installation: What It Actually Takes

About 1 in 5 Henderson homes I work on has a detached garage. The older Green Valley, Paradise Hills, and Whitney Ranch neighborhoods especially. Installing an EV charger in a detached garage is not just "longer wire." It involves trenching, sub-panels, load calculations, and an entirely different permit path. Here is what you need to know before calling anyone.

The Three Install Paths for Detached Garages

Depending on distance from the main house and the loads already in the garage, you pick one of three approaches:

1. Long feeder from main panel (short distances, small loads)

2. New sub-panel in the garage (most common, future-proof)

3. Dedicated service drop from NV Energy (rare, very large garages or workshops)

Path 1: Feeder From Main Panel

Works if the garage is under 75 feet from the main panel and you only need the EV charger (no lights, outlets, or other loads added).

What it looks like:

• 60A breaker in main panel
• 6 AWG copper wire (or 4 AWG for longer runs) in buried PVC conduit
• Junction box in garage
• Direct hardwire to Level 2 charger

Cost in Henderson 2026:

• Materials: $450 to $750
• Trenching (30 to 60 feet): $400 to $900
• Labor (6 to 10 hours): $750 to $1,400
• Permit: $110 to $165
• Total: $2,400 to $3,600

Limitation: You cannot add lights, outlets, or a shop vac circuit to this run. If the garage has no existing power, Path 2 is smarter.

Path 2: New Sub-Panel (The Common Choice)

This is what I recommend for 70 percent of detached garage EV installs. You run a heavier feeder (usually 100A) and install a small sub-panel in the garage. Then the EV charger is one circuit among several.

What it looks like:

• 100A breaker in main panel
• 1/0 AWG aluminum or 3 AWG copper feeder in buried PVC conduit
• 100A sub-panel mounted in detached garage (Square D QO130L125G or similar)
• 60A breaker + 6 AWG run to Level 2 charger
• Remaining space for lights, outlets, future workshop

Cost in Henderson 2026:

• Materials (feeder, sub-panel, breakers): $850 to $1,350
• Trenching (40 to 80 feet, 18 inches deep for PVC, 24 inches for direct burial): $650 to $1,450
• Core drilling through foundation (if needed): $150 to $350
• Labor (10 to 16 hours): $1,250 to $2,250
• Permit (two inspections: trench + final): $165 to $245
• Total: $3,600 to $5,900

Why it is worth the extra $1,200 to $2,300:

• You can add garage lighting, outlets, and workshop circuits
• A future second EV charger becomes a 2-hour install, not a repeat trench
• Resale value: buyers prefer garages with full electrical

Path 3: Dedicated Service Drop

Only makes sense for large detached workshops with multiple high-draw machines (welders, car lifts) plus EV charging, or when the main panel is already at or above capacity and a panel upgrade is not feasible.

Cost: $6,500 to $12,000+ depending on NV Energy coordination, transformer sizing, and meter base work.

Trenching: The Part That Surprises Homeowners

Henderson soil is desert alluvium with caliche layers (cemented calcium carbonate). Trenching 40 to 80 feet of it takes longer than people expect.

What we dig with:

• Hand trenching (under 30 feet, soft soil): 2 to 4 hours
• Mini trencher rental (Ditch Witch RT12, $275/day): 1 to 2 hours plus setup
• Backhoe (over 60 feet or hard caliche): $450 to $900 for half-day rental + operator

NEC 300.5 depth requirements:

• PVC conduit with 480V or less: 18 inches minimum cover
• Direct burial UF cable: 24 inches minimum cover
• Under driveway: 24 inches minimum

Blue Stake first. Nevada law (NRS 455) requires USA North 811 blue stake marking 2 business days before any digging. Free service. Skipping this and hitting a gas or water line results in fines plus repair bills.

Wire Sizing for Long Runs

Voltage drop matters for detached garages. NEC allows up to 3 percent voltage drop on feeders. At 240V that is 7.2 volts.

Typical sizing (copper, 60A load at 48A continuous):

• Under 40 feet: 6 AWG
• 40 to 80 feet: 4 AWG
• 80 to 150 feet: 2 AWG
• Over 150 feet: 1/0 AWG or switch to 100A feeder + sub-panel with aluminum

Aluminum feeders (SER or XHHW-2) save $200 to $600 on long runs. They are NEC-approved and perfectly safe with modern AL-CU rated connectors. We use them on most detached garage jobs over 60 feet.

Load Calculation: Do You Have Enough Panel Capacity?

Your main panel needs enough spare capacity to support a 60A or 100A new circuit. NEC 220.82 covers the calculation.

Typical Henderson single-family home loads:

• HVAC (3-ton, 240V): 40A demand
• Electric dryer: 30A demand
• Range: 40A demand
• Water heater (if electric): 25A demand
• Baseline lighting + outlets: 30A demand

A 200A panel with all-electric appliances often has 50 to 70A of spare capacity. Adding a 60A EV circuit fits. Adding a 100A sub-panel feeder pushes it, and panel upgrade may be needed.

On gas-heat, gas-dryer, gas-range homes, the math is almost always fine without an upgrade.

Permit and Inspection Path

City of Henderson treats detached garage EV installs as two separate work items:

1. Trench and conduit inspection: Scheduled before backfilling. Inspector verifies depth, conduit type, warning tape at 12 inches.

2. Final electrical inspection: After sub-panel and charger are installed, wired, and powered.

Expect 7 to 14 business days total from permit application to final sign-off. See our full permit guide.

Real Install Timeline

A typical detached garage install on a Henderson home:

• Day 1: Blue Stake ticket submitted
• Day 3: Permit application filed
• Day 5: Permit issued
• Day 6 or 7: Blue Stake marks visible, trench dug, conduit placed, wire pulled
• Day 7: Trench inspection (typically same-day or next-morning scheduling)
• Day 7 or 8: Trench backfilled
• Day 8 or 9: Sub-panel installed, charger mounted and wired
• Day 9 to 11: Final inspection
• Day 11: Charging

My Honest Advice

If your detached garage has no existing power, do not install just a minimum feeder. Spend the extra $1,500 for a sub-panel. You will use the outlets and lighting more than you expect, and the resale value is real.

If your garage already has a sub-panel, adding an EV charger is often a $900 to $1,500 job.

Henderson EV Charger Pros handles detached garage installs start to finish: Blue Stake, permit, trench, sub-panel, and charger. Call (838) 205-8397 for a free on-site assessment. We will walk the trench path with you and quote the exact scope.

Costs vary based on trench length, soil conditions, and existing garage electrical. All prices reflect Q2 2026 Henderson market.