Installing an EV charger at your home means choosing between running power lines underground or overhead—a decision that affects cost, aesthetics, safety, and long-term maintenance. The wiring method you select determines everything from permitting timelines to your landscape layout. Here's what you need to know before hiring an installer.
Underground Wiring: Pros and Cons
Underground conduit offers the cleanest look and eliminates overhead hazards like tree branches or weather exposure. Most homeowners prefer this method because it keeps the electrical lines hidden and protects them from UV damage and extreme temperature swings.
The trade-off is cost and installation complexity. You're looking at $2,000 to $5,000 extra compared to overhead installation because the electrician must dig trenches, lay conduit, and compact the soil properly. Depending on your soil type, drainage conditions, and distance from the breaker panel to the charger location, you might also face unexpected expenses if the contractor hits existing utilities or discovers poor soil conditions requiring reinforcement.
The timeline for underground installation typically runs 2 to 4 weeks versus 3 to 7 days for overhead, partly because of permit requirements and inspection waiting periods. If your property has a high water table or clay-heavy soil, costs can balloon an additional 20–30%.
Overhead Wiring: Speed and Budget
Overhead installation uses poles or mast-mounted conduit to run power lines from your main service panel to the charger. This method is faster and significantly cheaper—usually $500 to $1,500 less than underground options.
Electricians can typically complete overhead runs in a single day once permits are approved. You won't deal with trenching, soil compaction, or hidden utility risks. However, you'll see the conduit running across your roof or along the side of your home, which some homeowners find visually unappealing. Overhead lines are also more exposed to weather, UV rays, and potential damage from branches or storms.
Key Considerations Before Deciding
Distance from panel to charger location If your charger will be more than 100 feet from your main electrical panel, underground becomes more attractive because overhead poles become impractical and costly to install. Shorter distances favor overhead.
Local code requirements Some jurisdictions have strict rules about overhead lines near roofs, windows, or structures. Your local building department may effectively require underground in residential areas. Always check before committing to a method.
Soil conditions and utilities Before choosing underground, request a utility locate (typically free through Call Before You Dig). If your yard has clay, rocky substrate, or high water tables, underground costs spike. A soil test during the pre-installation survey costs $200–$400 but prevents surprises.
Future landscaping plans If you're planning to add a deck, pool, or significant landscaping, underground runs avoid conflicts later. Overhead wiring limits where you can install structures in your yard.
Budget and aesthetic priorities Underground costs more upfront but adds home value and keeps your exterior clean-looking. Overhead saves money now but requires ongoing visual tolerance of conduit running across your property.
Typical Installation Timeline
- Permit application: 3–7 days to 2 weeks depending on your jurisdiction
- Inspection scheduling: 1–3 weeks after submission
- Trenching or pole installation: 1–2 days for either method
- Conduit and wire installation: 1–3 days
- Final inspection: 1–5 days to schedule
- Total project: 3–7 weeks underground, 1–3 weeks overhead (both including permit and inspection waits)
Maintenance and Longevity
Underground conduit requires less maintenance once installed but costs more to repair if damage occurs—expect $1,500–$4,000 to excavate and replace damaged sections. Overhead conduit is easier and cheaper to access for repairs or upgrades, typically $300–$1,200 for fixes.
Both methods use durable PVC or HDPE conduit rated for 50+ years. The real difference is accessibility: overhead is simpler to maintain; underground is harder but safer from external interference.
Finding the Right Installer
Whichever route you choose, get quotes from at least three licensed electricians specializing in EV charger installation. Compare their soil surveys, timeline estimates, and warranty terms—not just price. Mercoly helps you compare and find trusted EV charger installation providers in one place, making it easier to evaluate your options side by side.
Frequently Asked Questions
Q: Can I switch from overhead to underground after installation? Yes, but you'll pay most of the original underground cost again plus disconnect and removal fees—typically $2,000–$4,500. Plan it right the first time.
Q: Does underground wiring need a permit while overhead doesn't? Both require permits in nearly all jurisdictions. Underground typically has longer permit review times because inspectors verify utility locates and soil conditions.
Q: Will my homeowners insurance affect which method I choose? Most policies cover both methods equally, but verify with your provider—some older policies have overhead restrictions in certain climates.
Contact three installers this week to request soil surveys and detailed quotes for your specific property layout.