Formula & constants
Installing EV charging infrastructure during construction costs roughly four to six times less than retrofitting it later. Removing and repairing 100–300 linear feet of surface parking to add conduit alone runs $11,500–$32,000 in demolition and repair, and about $7,000 per space can be avoided by pre-wiring. All default values are editable — when your supplier's data sheet or local code says otherwise, use that number.
Where this fits in your project
This tool is one step in a bigger job. Once you have these numbers, ev charging readiness calculator (EV Charging Readiness Calculator), then trench calculator (Trench Calculator). For the full sequence see the project workflows, compare approaches on the comparison pages, and check local factors in the state guides.
Frequently asked questions
How much more does an EV retrofit cost than pre-wiring?
Four to six times more. The premium comes from demolition, trenching and boring through finished pavement, circuit balancing, and a second round of permitting that new construction never pays.
What does trenching through existing pavement cost?
Removing and repairing 100 to 300 linear feet of surface parking typically costs $11,500 to $32,000 in demolition and repair, before any electrical work.
Is it worth pre-wiring spaces I do not need yet?
Usually yes if there is any expectation of future demand. Empty conduit and reserved panel capacity are cheap during construction; cutting open a finished lot is not.
Does conduit run length matter much?
Significantly. Every additional 50 feet adds both material cost and voltage drop. Clustering EV spaces near the electrical room or transformer is the cheapest design decision available.
Should I trench asphalt or concrete?
Asphalt is cheaper to cut and patch than concrete, but both are far more expensive than installing conduit before paving.
Last verified: — See our methodology.
Planning estimates only — confirm quantities with suppliers and local code before ordering.