What is the working stall pitch and drive-aisle geometry for a 4- to 8-stall DC fast-charger hub?

The honest working geometry for a public DC fast-charger hub in NC is an 11-foot stall pitch (center-to-center width of each parking bay), a 20- to 22-foot stall depth measured from the wheel stop or curb to the head-in-face of the equipment cabinet island, a 24- to 28-foot drive aisle behind the stall row for pull-out and reverse-in maneuvers, and a 5-foot clear buffer between the front of the stall (where the equipment cabinet or PSA cabinet sits) and the drive aisle on the opposite side. Pull-through stalls — increasingly required for tow-vehicle and trailer-EV compatibility — add 12 to 15 feet of front-side clearance to allow a truck-plus-trailer combination to pull straight through instead of reversing. The 11-foot pitch is wider than a standard parking bay (9 feet) because EV cable-management arms and connector pistols extend 3 to 5 feet from the equipment cabinet, and adjacent-stall connector clearance has to be maintained even when both stalls are simultaneously plugged in. The 24-foot drive aisle is one lane wider than a standard parking lot aisle (typically 22 feet) because reverse-in stall maneuvers with a passenger EV are slower than pull-in maneuvers with a gas vehicle.

How do we handle drainage on a multi-stall hub pad, and where does the water actually need to go?

Drainage on a DC fast-charger hub has three constraints that a standard parking-lot layout does not carry. (1) Water cannot pond under the equipment cabinets — the cabinets have NEMA 3R ratings for weather-exposed operation, but sustained standing water at the cabinet base plate accelerates gasket failure, ground-fault trip rates, and cabinet interior corrosion. (2) Water cannot flow across the ADA access aisles — a 1:48 (2.08 percent) maximum cross-slope combined with a runoff path through the aisle will send water pooling at the aisle low point and fail the ADA slope tolerance. (3) Water cannot flow into the trench-drain that carries the underground conduit runs — most vendor specs require a positive-drainage grade away from the trench cover to keep water out of the conduit runs and the cabinet interior. The working grade pattern: 1.0 to 1.5 percent slope away from the cabinet island in every direction, terminating at a perimeter curb or trench drain that carries runoff to a stormwater catch basin. Access aisles run 0.5 to 1.0 percent slope (below the 1:48 maximum) parallel to the stall length, never perpendicular. The stall bays themselves run 1.0 percent slope parallel to the parked vehicle centerline. All grade breaks land at joint lines in the concrete so the finish planes can be independently laser-screeded. On sites with tight grade constraints, a linear trench drain (NDS Dura Slope 12-inch or equivalent) at the front-of-stall face collects runoff before it reaches the drive aisle.

How do we tie canopy footings into the stall-bay slab without cracking the slab?

Canopy structures over DC fast-charger hubs — increasingly standard on Electrify America and NEVI-funded hub sites for weather protection and solar integration — impose two loads that a bare stall-bay slab does not carry. (1) Vertical footing loads at each canopy column (typically 15,000 to 40,000 pounds sustained plus wind uplift and snow-load reversals). (2) Torsional loads from wind on the canopy roof that push the column footings sideways relative to the surrounding slab. The wrong approach — casting the canopy column footings integrally with the stall-bay slab — puts the column point load into a slab that was not designed for point-load punching shear, and the slab cracks radially from the column within 12 to 24 months. The honest approach is a separately poured, isolated column footing at each column: 4-foot by 4-foot by 3-foot-deep reinforced pier per column, isolated from the surrounding stall-bay slab with a 1/2-inch expansion-joint filler and a bond-breaker sheet on the vertical face. The stall-bay slab pours around the isolated footings, control joints radiate away from each column corner at 45-degree angles to relieve stress concentration, and the column footings carry their own load path through the pier down to bearing capacity. On a 6-stall hub with a full canopy (typical: 4 columns), the layout carries 4 isolated column piers, 6 stall-bay slabs jointed against the piers, and a 10-inch cabinet island slab all pouring in a single mobilization. Same freeze-thaw and mix discipline as our Tesla Supercharger pad spec applies to the whole footprint.

What does a 4-, 6-, or 8-stall DC fast-charger hub pad cost per stall in NC in 2026?

Turnkey concrete scope on a multi-stall DC fast-charger hub in NC in 2026 runs $9,500 to $18,000 per stall depending on hub size, ADA scope, drainage complexity, and canopy integration. The 2026 working ranges: 4-stall hub with shared cabinet island and 1 ADA-accessible stall $42,000 to $65,000 turnkey (concrete only, not including trenching, electrical, or equipment). 6-stall hub with shared cabinet island, 2 ADA-accessible stalls, and drive-aisle re-integration $65,000 to $95,000 turnkey. 8-stall hub with shared cabinet island, 2 ADA-accessible stalls, drive-aisle re-integration, and canopy footings $85,000 to $135,000 turnkey. Site work adds materially: saw-cut and tearout of existing lot for an in-parking-lot integration $8 to $16 per SF, subgrade correction on soft soils $6 to $12 per SF, trench-drain install at the cabinet perimeter $85 to $140 per linear foot, canopy column pier install (separately poured) $2,800 to $4,500 per column, laser-screed pour premium for ADA aisle tolerance $1.20 to $2.00 per SF above standard-finish pour pricing. NEVI-funded sites requiring reimbursement audit documentation add 8 to 12 percent to concrete scope for compaction testing, cylinder-break records, and as-built survey documentation. Site-acceptance rework on failed ADA slope or failed cabinet drainage adds $8,000 to $22,000 per stall — which is why the pre-pour laser layout, the as-built grade survey, and the pre-pour ADA slope verification are non-negotiable line items on our scope.

EV Charging Hub Layout: 4-8 Stall Concrete Pad Spec

Quick answer: The working geometry for a 4-, 6-, or 8-stall public DC fast-charger hub in NC is an 11-foot stall pitch, a 20- to 22-foot stall depth, a 24- to 28-foot drive aisle behind the stall row, 2 ADA-accessible stalls per 8-stall hub with 5-foot and 3-foot access aisles at plus-or-minus 1/16 inch flatness, 1.0 to 1.5 percent drainage grade away from the shared cabinet island, an 8-inch reinforced stall-bay slab on 8 inches of ABC stone, a 10-inch cabinet island pad with #5 rebar at 10-inch centers, isolated canopy column footings poured before the stall-bay slab, and a 4,500 PSI air-entrained mix across the whole footprint. Turnkey NC pricing runs $9,500 to $18,000 per stall for the concrete work only. Get the layout right on the front end and everything else — vendor equipment install, NEVI reimbursement audit, ADA site walk, and 5-year operations reliability — becomes downstream sequencing instead of expensive rework.

Multi-stall hubs are a layout problem before they are a slab problem

The concrete scope on a 4- to 8-stall DC fast-charger hub is not fundamentally different from the single-cabinet Tesla Supercharger scope we cover in our Tesla V3/V4 pad spec guide. The stall-bay thickness, the cabinet-pad reinforcement, the conduit stub-out geometry, and the grounding pattern are all similar problems at similar scale. What is different — and what determines whether the site succeeds or requires $20,000 to $60,000 in post-pour rework — is the layout.

A multi-stall hub has to satisfy five geometric constraints simultaneously. The stall pitch has to hold enough clearance for cable-management arms at adjacent stalls to swing without collision. The drive aisle has to be wide enough for reverse-in maneuvers with a passenger EV at typical 2026 turning-radius specs. The ADA-accessible stalls have to hit the 5-foot and 3-foot access-aisle widths with cross-slope and running-slope tolerances tighter than a standard parking-lot finish. The drainage grade has to run away from the equipment cabinets in every direction while staying below the ADA slope tolerance at the access aisles. The canopy footings — if the site is canopied, which most Electrify America and NEVI-funded builds now are — have to isolate from the stall-bay slab so the vertical column loads do not crack the slab.

Miss any one of those constraints on the front end and the failure mode is expensive. Fail the stall pitch and adjacent-stall cable clashes force cable pigtail replacements. Fail the drive aisle and the site fails commissioning. Fail the ADA slope and the site fails DOJ walk-through and blocks NEVI reimbursement. Fail the drainage and the cabinets accumulate standing water and start tripping on ground faults. Fail the canopy footing isolation and the slab cracks around every column within 12 to 24 months. The layout is the make-or-break line item.

11-foot stall pitch and 24-foot drive aisle: the working geometry

The honest working stall pitch for a public DC fast-charger hub in NC is 11 feet center-to-center — wider than the 9-foot standard parking bay and wider than the 10-foot Tesla Supercharger stall pitch. The extra 12 to 24 inches per stall carries three loads: cable-management arm clearance for adjacent stalls plugged in simultaneously (the CCS and NACS connector cables plus the ChargePoint proprietary connectors are stiffer and less flexible than the Tesla cable, and the swing clearance is meaningfully greater); access-side clearance for the driver's door open on a passenger EV parked at the wheel stop; and buffer for future connector-standard changes (NEVI-funded sites have to accommodate CCS1, NACS, and legacy CHAdeMO on some installations, which means multiple connector positions per cabinet).

The stall depth is 20 to 22 feet measured from the wheel stop at the front of the stall to the cabinet-island face at the head-in end. That depth accommodates the full range of 2026 passenger EVs (compact hatchbacks at 165 inches through full-size SUVs and pickup trucks at 245 inches) with 24 to 32 inches of front-vehicle-to-cabinet clearance for cable reach and driver walk-around. Pull-through hub layouts — increasingly required for tow-vehicle and trailer-EV charging — add 12 to 15 feet of front-side clearance so a truck-plus-trailer combination can pull straight through without reversing.

The drive aisle behind the stall row runs 24 to 28 feet wide — one lane wider than a standard parking-lot aisle. The extra width is not decorative: reverse-in stall maneuvers with a passenger EV are slower and less precise than pull-in maneuvers with a gas vehicle, and the industry's operational data shows a meaningful uptick in stall-cabinet impact rates on aisles narrower than 24 feet. The 28-foot spec is used on high-traffic hubs (Concord Mills, Brier Creek, Friendly Center) where simultaneous multi-stall reverse-in maneuvers happen on peak-load days.

ADA scoping: 2 accessible stalls per 8, with 1/16-inch flatness

The current NEVI standard and the emerging federal DOJ ADA guidance require accessible EV charging stalls at a ratio of at least 2 accessible stalls per 8-stall hub. On a 4-stall hub the requirement is 1 accessible stall. On a 6-stall hub the requirement is 1 accessible stall (with 2 accessible strongly recommended for NEVI reimbursement). On an 8-stall hub the requirement is 2 accessible stalls — 1 van-accessible with a 60-inch (5-foot) access aisle on the passenger side and 1 standard-accessible with a 36-inch (3-foot) access aisle on the passenger side.

The van-accessible stall must be 132 inches (11 feet) wide, must carry a 96-inch (8-foot) vertical clearance from the pad surface to any canopy structure, and must sit adjacent to a 60-inch access aisle finished to plus-or-minus 1/16 inch flatness across the aisle width. The standard-accessible stall must be 132 inches wide with a 36-inch aisle on the passenger side, same 1/16-inch flatness tolerance. Access aisles cannot be used as parking stalls, cannot be used as drive-through paths, cannot slope more than 1:48 (2.08 percent) cross-slope, and cannot slope more than 1:48 running slope.

The concrete finish tolerance is the tight line item. A 1:48 slope over a 60-inch aisle allows 1.25 inches of drop across the aisle width — which sounds generous until you check the concrete-finish plus-or-minus tolerance and realize a standard parking-lot pour finished to plus-or-minus 1/4 inch can drift into slope non-compliance on a single high spot. Hitting 1/16-inch tolerance across each access aisle requires a laser-screed pour with a bump-cutter finish pass, not a bull-float finish. The laser-screed premium runs $1.20 to $2.00 per SF above standard-finish pricing — worth every dollar to clear the ADA walk on the first pass instead of grinding out a rework.

Drainage: 1.0-1.5 percent away from cabinets, flat at ADA aisles

Drainage on a DC fast-charger hub carries three constraints that a standard parking-lot layout does not. Water cannot pond under the equipment cabinets — sustained standing water at the cabinet base plate accelerates gasket failure, ground-fault trip rates, and cabinet interior corrosion, all of which push the cabinet's operational reliability below the hub-operator's 99-plus percent uptime SLA. Water cannot flow across the ADA access aisles at anything above the 1:48 slope. Water cannot flow into the trench-drain that carries the underground conduit runs, because water in the conduit trench pushes moisture into the cabinet interior and creates ground-fault paths.

The working grade pattern: 1.0 to 1.5 percent slope away from the cabinet island in every direction, terminating at a perimeter curb or a linear trench drain (NDS Dura Slope 12-inch or equivalent) that carries runoff to a stormwater catch basin. Access aisles run 0.5 to 1.0 percent slope parallel to the stall length, never perpendicular. Stall bays run 1.0 percent slope parallel to the parked vehicle centerline. Grade breaks land at joint lines in the concrete so the finish planes can be independently laser-screeded. On sites where the existing lot grade fights the required drainage direction — common on infill hubs — a linear trench drain at the front-of-stall face collects runoff before it reaches the drive aisle and the ADA access aisles.

The low-shrinkage mix discipline from our high-PSI data-center floor guide applies here — a shrinkage-reducing admixture in the pad mix keeps crack widths tight around the trench-drain edges and the cabinet-island perimeter, both of which are drainage-critical joints.

Cabinet island: 10-inch slab with #5 rebar at 10 inches

The shared cabinet island on a multi-stall hub — the pad that carries the Electrify America, EVgo, ChargePoint, or Francis Energy consolidated power cabinets that service all stalls — is a separately reinforced slab set at the head or center of the stall row. The working spec is a 10-inch slab minimum on 10 inches of compacted ABC stone, reinforced with #5 rebar at 10 inches on center each way, poured 4 to 6 inches above the surrounding stall-bay finish grade so the cabinet base plates stay out of standing water.

Cabinet weights and anchor-bolt loads vary meaningfully by vendor. Electrify America's Hyper-Fast (350 kW) cabinets weigh 4,500 to 6,500 pounds fully loaded. EVgo's Kempower cabinets weigh 3,000 to 4,500 pounds. ChargePoint Express 250 cabinets weigh 2,800 to 3,800 pounds. Francis Energy's Delta Electronics-based cabinets weigh 3,500 to 5,500 pounds. Anchor-bolt pull-out tension varies from 8,000 pounds (ChargePoint) to 14,000 pounds sustained (Electrify America Hyper-Fast under wind loading in coastal NC). The 10-inch slab with #5 rebar at 10-inch centers clears the highest anchor-bolt pull-out spec (14,000 pounds) across every vendor's cabinet, which lets the same concrete pour serve any future cabinet swap without slab re-engineering.

The anchor-bolt pattern is set into the rebar cage before the pour, with the anchor bolts pre-positioned to the vendor's base-plate template. Pull the vendor design package before the rebar tie-in and set the geometry with laser layout, not tape measure. The same pre-pour verification discipline we apply on residential slab work in our final-payment inspection checklist scales up: photograph and dimensioned-verify every anchor bolt and every conduit stub against the design package before the pour releases.

Canopy footings: isolated column piers, not integral with the slab

Canopy structures over DC fast-charger hubs are increasingly standard — Electrify America's 2024-forward hub designs include weather-protection canopies by default, and NEVI-funded builds with solar integration require canopy structures for the PV panel mounting. The canopy loads impose two problems on the concrete: vertical column point loads of 15,000 to 40,000 pounds sustained per column, plus torsional loads from wind on the roof structure that push the column footings laterally relative to the surrounding slab.

The wrong approach is casting the canopy column footings integrally with the stall-bay slab. The stall-bay slab is not designed for point-load punching shear, and the concentrated column load will crack the slab radially from the column base within 12 to 24 months. The honest approach is a separately poured, isolated column footing at each canopy column: 4-foot by 4-foot by 3-foot-deep reinforced pier per column, isolated from the surrounding stall-bay slab with a 1/2-inch expansion-joint filler and a bond-breaker sheet on the vertical face. The stall-bay slab pours around the isolated piers, control joints radiate away from each column corner at 45-degree angles to relieve stress concentration, and the piers carry their own load path through the pier down to bearing capacity.

The sequencing matters. Pour the isolated column piers first, cure to 7 days at 4,500 PSI, then pour the stall-bay slab around them. Trying to pour everything in one operation and expecting the joint filler to isolate the loads is not the path — the wet concrete in the stall-bay slab bonds to the pier faces through the joint filler compression, and the isolation fails at cure. The two-pour sequence adds 7 days to the pour schedule and eliminates the point-load slab cracking that would otherwise force a full pad rebuild by year 3.

NC market notes

Three regional patterns shape multi-stall hub work across the state.

The Charlotte / Concord I-85 corridor. Highest density of NEVI-designated corridor sites in the Carolinas and highest hub-scale build volume. Electrify America, EVgo, and ChargePoint all run 6- to 8-stall hub sites at Concord Mills, University City, and I-85 pull-offs. Cabarrus and Mecklenburg engineering reviews run 10 to 15 business days for hub-scale EV permit packages, with the ADA slope tolerance verification as a separate 3- to 5-business-day submittal. Carolina Sunrock and Vulcan both carry the 4,500 PSI air-entrained mix at hub-scale volume.

The Greensboro Triad NEVI corridor. PTI-adjacent, Friendly Center, and Winston-Salem east-side interchanges carry the majority of Triad hub-scale builds. Guilford and Forsyth county permit review is faster than the Charlotte corridor (7 to 10 business days) but the ADA walk-through is stricter, with a documented history of pushing sites back for cross-slope non-compliance that would have cleared in Charlotte. Laser-screed pours are the default here, not the premium option.

The I-77 mountain-approach corridor. Hickory, Statesville, Mooresville hub sites carry Charlotte-to-Asheville corridor traffic. Iredell and Catawba county permit review runs 5 to 10 business days. The freeze-thaw cycling on the mountain approach is meaningfully harsher than the Piedmont sites — up to 60 freeze-thaw cycles per winter in the Hickory-to-Statesville band versus 25 to 35 in Charlotte — so the air-entrainment spec runs at the top of the 5-to-7 percent range and the ADA aisle finish requires 72-hour cure protection through the first cold snap after pour.

Frequently asked questions

Can we pour a 4-stall hub in phases if the site is an existing lot?

Yes. Phased pours are the working answer on in-lot hub retrofits where the operations manager cannot lose all 4 stalls simultaneously. Pour 2 stalls plus the shared cabinet island in phase 1, cure to 7 days, open to charging traffic, then pour the remaining 2 stalls in phase 2. The joint between phase 1 and phase 2 pours is doweled at 12-inch centers with #4 dowel bars — same load-transfer detail we cover on our phased warehouse lot replacement playbook.

Does the hub pad qualify for a NEVI reimbursement audit?

Yes, on sites that meet the NEVI site-eligibility criteria (50-mile-alternating-fuel corridor location, 150-kW-minimum-per-stall capacity, 4-stall-minimum hub, ADA-accessible stalls at the required ratio). NEVI reimbursement requires as-built documentation on the concrete work: subgrade compaction testing, cylinder-break records at 7 and 28 days, ADA slope survey at commissioning, and vendor-approved anchor-bolt pull-out testing. We produce the full audit package as part of the concrete scope on NEVI-eligible sites.

What is the difference between the cabinet-island footprint on Electrify America vs EVgo vs ChargePoint?

Electrify America Hyper-Fast (350 kW) cabinet island typically 8 feet by 14 feet for a 4-stall power block. EVgo Kempower modular cabinet island typically 6 feet by 12 feet for a 4-stall block. ChargePoint Express 250 cabinet island typically 5 feet by 10 feet for a 4-stall block. Francis Energy Delta Electronics-based cabinet island typically 6 feet by 12 feet for a 4-stall block. The 10-inch slab spec with #5 rebar at 10-inch centers clears the anchor-bolt pull-out spec across all four vendors, so the same concrete pour serves any future vendor swap.

Do we need a stormwater permit for the hub pad?

Sites under 1 acre of disturbed area typically clear NC stormwater at the local municipal level with a simple erosion-control plan. Sites above 1 acre require NCDEQ stormwater plan review, which runs 30 to 60 days on top of the local permit. Most 4- to 8-stall hub builds land below the 1-acre threshold when slotted into an existing parking lot; bare-lot NEVI hub builds with canopy structures frequently trip the 1-acre threshold and require the state review.

What warranty do we carry on multi-stall hub concrete?

10-year material-and-labor warranty on the stall-bay slab and cabinet-island slab. 5-year warranty on anchor-bolt pull-out capacity and canopy pier isolation. 3-year warranty on ADA slope tolerance across access aisles. 2-year warranty on drainage performance at the cabinet perimeter. The warranty covers slab settlement, cabinet-corner cracking, canopy pier separation, ADA slope drift, and cabinet-perimeter ponding.

Key takeaways

11-foot stall pitch, 20- to 22-foot stall depth, 24- to 28-foot drive aisle. Wider than standard parking-lot geometry for cable clearance and reverse-in maneuvering.
2 ADA-accessible stalls per 8-stall hub, 1 van-accessible with 5-foot aisle plus 1 standard-accessible with 3-foot aisle. Access aisles finished to plus-or-minus 1/16 inch flatness for 1:48 slope compliance.
1.0 to 1.5 percent drainage grade away from the cabinet island in every direction. Access aisles below 1:48. Linear trench drain at cabinet perimeter where existing grade fights required direction.
10-inch cabinet-island slab with #5 rebar at 10 inches on center serves Electrify America, EVgo, ChargePoint, and Francis Energy cabinets with the same reinforcement spec. 14,000-pound anchor-bolt pull-out clears every vendor.
Isolated column piers for canopy structures, poured before the stall-bay slab. Bond-breaker at the pier face plus radiating control joints at column corners. Integral column pours crack the slab within 12 to 24 months.
4,500 PSI air-entrained mix at 5 to 7 percent air, laser-screed pour with bump-cutter finish across ADA aisles. Standard bull-float finish drifts out of 1:48 slope tolerance and forces rework.
Pay nothing until the work is complete. We close out the pre-pour laser layout, the anchor-bolt template verification, the ADA slope survey, and the NEVI audit documentation before invoicing.

Ready to lay out and pour a 4-, 6-, or 8-stall public DC fast-charger hub — Electrify America, EVgo, ChargePoint, Francis Energy, or NEVI-funded — on an NC parcel? Call Local Concrete Contractor at (704) 318-2440 or request a no-deposit multi-stall hub scope review and we will line-item the stall geometry, ADA layout, drainage grade, cabinet-island reinforcement, canopy pier isolation, and NEVI audit documentation against the vendor design package before mobilization.