Very-narrow-aisle (VNA).
5–6 ft aisles. Up to 45 ft height. Wire-guided or rail-guided. The max-cube system for warehouses where every square foot has to earn rent.
Height over aisle width.
VNA narrows the working aisle to 5–6 ft and pushes the racking up — commonly 30–45 ft — so the cube you can't get sideways, you get vertically. You keep 100% selectivity: every pallet stays directly accessible, unlike drive-in or push-back.
The trade is the truck. VNA runs on rail-guided or wire-guided forklifts — turret trucks and SOTOs that stay centred in the narrow aisle. The floor slab, guidance system, and rack design are engineered together as one system.
The components, labeled.
Upright Frame
Structural C-channel frame, 11ga steel. Required for VNA height — taller frames load-multiply at the base.
Step Beam
Heavy-duty step beam. Same connection as selective, but tighter aisle tolerances require beam-end pinning + double-locking.
Guide Rail (Floor-mounted)
Steel angle anchored to the floor along each aisle. Forklift's bottom rollers track the rail — keeps forklift centred in the narrow aisle.
Wire Guidance (Optional)
Inductive wire buried in the floor slab. Forklift's antenna reads the wire signal. Smoother than rail; required for SOTOs (Stand-On Turret Trucks) at full height.
Footplate (Reinforced)
Larger footprint than selective — VNA load multiplication at the base requires a wider plate + additional anchor bolts.
Anchor Bolt
Larger gauge anchor (5/8" minimum). Embedment depth ≥ 5" into 6" minimum slab — slab spec is part of every VNA design review.
Aisle Protection
Steel pillar guards at every aisle entry. Required to prevent forklift-frame contact damage in narrow aisles.
Why very-narrow-aisle (VNA)?
Because square-foot rent forces you upward. VNA converts 30% wider aisles into 30% more vertical storage. The right choice when you can't expand horizontally and need 100% selectivity at height.
Full technical detail.
| Specification | Standard VNA | Heavy VNA | Max-Bay VNA |
|---|---|---|---|
| Aisle & Height | |||
| Aisle width | 5'-6' | 5'-6' | 5'-6' |
| Max height | 30' | 40' | 45' |
| Guidance | Rail-guided | Rail or wire-guided | Wire-guided |
| Frame & Beam | |||
| Post profile | 3" structural | 3" structural | 3.5" structural |
| Post gauge | 12ga | 11ga | 10ga |
| Beam profile | Heavy step beam | Heavy step beam | Structural C-beam |
| Capacity (Beam Pair) | |||
| Beam pair capacity | 3,800 lb | 4,500 lb | 5,500 lb |
| Frame capacity | 30,000 lb | 45,000 lb | 60,000 lb |
| Slab & Anchors | |||
| Slab spec | 6" min, 3,500 PSI | 6" min, 4,000 PSI | 8" min, 4,000 PSI |
| Anchor size | 5/8" | 5/8" | 3/4" |
| Anchors per footplate | 4 | 4 | 6 |
| Finish & Compliance | |||
| Finish | Powder-coat or galv | Powder-coat or galv | Galvanized |
| CSA A344-17 aligned | ✓ | ✓ | ✓ |
| ANSI MH16.1 (RMI) certified | ✓ | ✓ | ✓ |
| Operations | |||
| Lead time | 3-4 weeks | 4-5 weeks | 5-7 weeks |
| Install crew size | 4-5 | 5-6 | 6-8 |
| Permit required | Usually | Yes | Yes |
Send your warehouse dimensions + SKU profile + throughput target. We'll come back with a stamped layout + itemized quote within 5 business days. Or grab the VNA Spec Sheet above to size it yourself — every layout load-rated to CSA A344-17.
Where very-narrow-aisle (VNA) wins.
Max-cube warehouses
When square-foot rent is the binding constraint. VNA converts 30% wider aisles into 30% more vertical storage.
Mixed-SKU + height-extreme
Where you need 100% selectivity AND height utilization. VNA preserves selective access while doubling stack height.
Automation-ready
VNA's strict aisle tolerances are the same tolerances autonomous mobile robots (AMRs) need. Easier upgrade path than wide-aisle selective.
VNA vs. the alternatives.
Max cube + selectivity
5–6 ft aisles, up to 45 ft. 100% selectivity, guided trucks. Best when you can't expand sideways.
This productFull selectivity
Wide aisles, standard reach trucks. Every pallet accessible. Industry standard, 3–5 day lead.
View product →Density + pick speed
2–6 deep, LIFO, single-aisle access. +90% vs selective. Faster to pick than drive-in.
View product →
STOCK · loaded high-bay aisle · swap in Sprint RWhere VNA earns its keep.
GTA warehouses where horizontal expansion is off the table and the clear height is there to use. Square-foot rent is the binding constraint, the SKU mix needs full selectivity, and the floor can take a guided truck. VNA gives you the cube without giving up access to any pallet.
It's also the cleanest on-ramp to automation: the tight aisle tolerances VNA already demands are the same ones autonomous mobile robots need, so the upgrade path is shorter than from wide-aisle selective.
Build your VNA layout.
Send your warehouse dimensions and we'll come back with a stamped layout + itemized quote. Pick your space, watch it assemble, and get a ballpark in 60 seconds.
60 seconds · no obligation · across the GTA · (647) 692-4416