CALGreen 2022 EV parking requirements by occupancy type — exact percentages, conduit sizing, panel capacity, and how local Bay Area jurisdictions make...

CALGreen 2022 defines three EV infrastructure tiers — EV Capable, EV Ready, and EVSE — each calculated as a percentage of total parking by occupancy type. The math is rarely the hard part. The hard part is the conduit routing and the panel capacity that the percentages quietly demand.

The Three Tiers of EV Infrastructure

CALGreen 2022 defines three tiers of EV infrastructure, each with different requirements: EV Capable, EV Ready, and EVSE (Electric Vehicle Supply Equipment). Understanding the distinction is critical for site planning because each tier has different implications for electrical panel sizing, conduit routing, and parking lot layout.

EV Capable means conduit and panel capacity are installed, but no wiring or charger. It's future-proofing: the infrastructure is in place so a charger can be added later without tearing up the parking lot. EV Ready means the conduit, wiring, and dedicated circuit are installed up to a junction box at the parking space — just add the charger. EVSE means a fully operational charging station is installed and energized on day one.

How to Calculate the Numbers

The required number of EV spaces depends on the occupancy type and total parking count. For multifamily residential, CALGreen 2022 requires 40% EV Capable, 10% EV Ready, and 5% EVSE (Level 2) for projects with 20+ units. For commercial office, the split is different: 30% EV Capable, 10% EV Ready, and the first space EVSE. These percentages apply to the total number of parking spaces provided, not the code minimum.

The math gets complicated when you layer in local amendments. San Francisco, San Jose, and several other Bay Area cities have adopted stricter requirements than the state baseline. San Jose, for example, requires 100% EV Ready for residential projects — every single parking space must have a dedicated circuit. This dramatically increases the electrical panel size and the amount of conduit in the parking structure or surface lot.

The Electrical Engineering Impact

EV infrastructure requirements are reshaping electrical service design. A 100-unit apartment building with 100% EV Ready spaces may need an additional 400–600 amps of electrical capacity just for EV charging. That's on top of the building's HVAC, lighting, and domestic loads. In many cases, the EV load pushes the total service requirement from a standard 2,000-amp service to 3,000 amps or more, which changes the transformer size, the switchgear configuration, and potentially the utility service lateral from the street.

The civil engineer's role is coordinating the conduit routing from the electrical panels to the parking spaces. In a surface parking lot, this means trenching conduit runs under the paving — typically 2-inch PVC conduits, one per circuit, running from a central panel location to junction boxes at each EV space. The conduit layout has to be coordinated with the storm drain, water, and sewer utilities to avoid conflicts at crossings.

Practical Design Tips

Cluster the EV spaces near the electrical room or transformer to minimize conduit run lengths. Every additional 50 feet of conduit run adds cost and voltage drop. On large surface lots, consider a distributed panel approach with sub-panels located at multiple points in the lot rather than running every circuit from a single location.

Design the conduit routing on the grading plan, not as a separate electrical drawing. The civil engineer controls the trench depths and crossing elevations. If the EV conduit crosses the storm drain main at the same depth, one of them has to move — and that decision needs to happen during design, not during construction.

The Bottom Line

Every project has its own constraints — site geometry, soil conditions, agency jurisdiction, schedule pressure. What doesn't change is the physics: water flows downhill, utilities need clearance, and code requirements aren't negotiable. The projects that go smoothly are the ones where the civil engineer is involved early enough to shape the site plan around these realities rather than retrofitting solutions after the architecture is locked.

At Calichi Design Group, we've built our practice around getting these details right the first time. Our team has permitted projects in dozens of jurisdictions across the West Coast and Pacific, and we know which agencies want what, which reviewers flag what, and which shortcuts actually cost more time than they save.

If you're starting a project and want to avoid the most common civil engineering pitfalls, reach out for a conversation. We'll give you an honest assessment of what your site needs and a fixed-fee proposal — usually within a week.