Installing an EV Charger in a Detached Garage: Trenching, Conduit, and Sub-Panels in Pittsburgh

By pwsadmin | July 15, 2026

A lot of Pittsburgh homes have a detached garage at the back of the lot, an alley or driveway between, and an EV that needs charging. The electrical path from your main panel to the car is rarely short and almost never simple. Here’s how we approach detached-garage EV installs, what it costs, and the decisions that have the biggest impact on the final price.

The three ways to get power to a detached garage

Direct-buried trenched wire: lowest cost, works for shorter runs
PVC conduit trenched: slightly more, much easier to add or repair later
Overhead service: sometimes mandated by local code, sometimes the cheapest option

In city Pittsburgh, overhead service between buildings is rare because of the density and the lot layout. Most detached garages get trenched feeders.

Direct-buried wire

USE-rated underground cable can be buried directly in the ground at 24 inches of depth for most residential applications. It’s the cheapest option but has a few tradeoffs. If a future homeowner plants a tree right on the line, or the city cuts a utility, the cable is hard to access. You’re also locked in to whatever capacity you spec today.

For most Pittsburgh backyards, direct-burial works fine. Cost is largely driven by distance: call it $15 to $25 per foot for the feeder wire plus labor, not counting the sub-panel and the breaker work on either end.

PVC conduit (our default recommendation)

Schedule 40 or Schedule 80 PVC conduit buried at 18 inches, with individual THHN conductors pulled through. It costs 20 to 40 percent more than direct burial up front. The payoff is that if you ever want to add more circuits, or the wire fails, or the code changes, you pull and re-pull. We call this future-proofing for very real reasons: we’ve come back to houses 10 years after an EV install and added a hot tub circuit through the same conduit.

Trenching logistics

The trench between the house and the garage usually crosses grass, a driveway, or a patio. Each one has a different cost profile:

Grass yard: cleanest. We can trench with a small machine or by hand depending on length. Sod gets re-laid after.
Driveway or sidewalk: we either go around (longer trench but cheaper) or we saw-cut and patch (shorter but $200 to $500 in concrete or asphalt work).
Under a deck or over existing utility lines: often requires a PA One Call locate before any digging, which is free but takes 2 business days. We always make that call.

Ground conditions matter too. Pittsburgh clay in late summer is brutal. We’ve been on jobs where a 30-foot trench took 6 hours because of rock. If we do the walkthrough in June and you schedule for August, we’ll sometimes recommend pulling the trench earlier before the ground hardens.

Sub-panel sizing

For a detached garage with an EV charger plus lights and a couple of outlets, a 60-amp sub-panel is the minimum. If you’re planning for future loads (welder, air compressor, mini-split heat, second EV), go with 100 amps. The feeder gauge and the breaker size at the main panel scale up accordingly.

A few real-world Pittsburgh detached-garage builds we’ve quoted recently:

Squirrel Hill two-car detached, 45 feet from main: 60-amp sub-panel, EV charger hardwired, two LED shop lights, three outlets. Total $3,800, including trenching.
Mount Lebanon detached with workshop, 60 feet from main, driveway crossing: 100-amp sub-panel, EV charger, welder circuit, dust collector, 8 outlets, shop lights. $5,400, including saw-cut and patch on the driveway.
Brookline detached behind a rowhouse, 25 feet from main, grass only: 60-amp sub-panel, EV charger, basic lighting. $2,900.

What surprises people

The trench is not the expensive part. The expensive parts are the sub-panel, the feeder breaker at the main, the dedicated ground rod at the garage, the EV charger itself, and the permits. For most quotes, trenching is about 15 to 25 percent of total cost. The rest is materials and labor on either end.

If the house’s main panel is near capacity, you may need a panel upgrade to feed the garage at all. That’s a separate conversation and it often pushes the total project over $7,000. We do the load calculation before quoting so there are no surprises.

Permits and inspection

Detached-garage sub-panels always require a permit. Allegheny County or city of Pittsburgh permit fees for a feeder install + sub-panel + EV circuit usually run $200 to $400. Inspection happens after the conduit is open and before backfill, then a final inspection after the sub-panel and charger are energized.

Don’t let anyone skip the permit on this kind of work. Buried feeders are exactly the thing a home inspector will flag on resale, and unpermitted electrical can be an insurance issue if anything goes wrong.

Walk the site first

Every detached-garage EV quote we give starts with a site walk. We look at the panel, the garage, the path between them, the gas meter, the utility drop, and the grade. Ten minutes of walking saves us from quoting wrong. If you’re thinking about it, book a walkthrough and we’ll give you a straight, itemized number.

Frequently Asked Questions

How do you run power to a detached garage for EV charging?

Most detached-garage EV installs use a trenched underground feeder (UF cable or THWN in PVC conduit) from the main panel to a sub-panel in the garage. The sub-panel then feeds the EV charger plus any other garage circuits. Trench depth is the main cost driver.

Does an underground EV charger circuit need conduit?

UF cable can be direct-buried at 24 inches, but most Pittsburgh installers prefer Schedule 40 PVC conduit — it protects the wire, simplifies future upgrades, and allows shallower burial (18 inches for PVC under concrete, 12 inches under rigid metal conduit with GFCI protection).

How deep does the EV charger trench need to be?

Per NEC 300.5, residential direct-buried UF cable needs 24 inches of cover; PVC conduit with a GFCI-protected 120V/240V circuit needs 18 inches. Rigid metal conduit can go as shallow as 6 inches if it’s under a building. A licensed installer confirms local requirements at permit pull.

Need a Licensed Pittsburgh Electrician?

Renaissance Electric & Power Systems has been serving Pittsburgh homeowners since 2008 with licensed, insured work backed by our PA contractor registration (PA-032900). Whether you need a panel upgrade, EV charger installation, recessed lighting, or whole-home surge protection, we handle it start-to-finish.

Call 1-888-681-WIRE (9473) or request a free estimate.

Service areas: Pittsburgh, Mt. Lebanon, Upper St. Clair, Bethel Park, Peters Township, Fox Chapel, Sewickley, Robinson Township, McCandless, Franklin Park, Hampton Township, O’Hara Township, Edgeworth, Sewickley Hills, and Bell Acres.

Posted in EV Charging