A rack and truck layout with very narrow aisles, often about 5 to 6 feet wide, served by specialized trucks such as turret trucks or man-up order pickers to maximize storage density.
Detailed Definition
Very narrow aisle (VNA) storage cuts aisle width down close to the width of the truck and its load, so more rack fits on the same floor area. Because trucks cannot turn in the aisle, VNA uses turret trucks that rotate their forks, or man-up order pickers that pick cases from the aisle. Trucks are usually guided by a wire in the floor or by rails on the rack. VNA is often combined with tall rack to use building height as well as floor space.
What it takes to run VNA
- Floors flat and level enough for high lift heights, often to a tighter specification than a standard warehouse floor.
- Guidance in each aisle, either a buried wire or rails along the rack base.
- Rack designed for the truck, with clearances agreed by the truck and rack suppliers.
- Pick-up and drop-off stations at aisle ends so other trucks can feed pallets in and out.
- Fire protection and lighting planned for narrow, tall aisles.
Trade-offs compared with wider aisles
VNA gives more pallet positions per square foot than selective rack served by reach trucks or counterbalanced forklifts, while keeping every pallet directly accessible. In exchange, the trucks cost more, move between aisles more slowly and can become a bottleneck if one is down. Layouts are hard to change once guidance and floors are set, so VNA suits stable, high-volume storage better than operations that change often.
Pallet quality at height
Damaged pallets cause more trouble in tall, tight aisles. Broken bottom boards, protruding nails or loose wrap can snag on rack or drop debris into the aisle. Many VNA sites inspect inbound pallets and restack poor ones onto sound pallets before putaway.
Related Glossary Terms
Frequently Asked Questions
How narrow is a very narrow aisle?
There is no single official definition. VNA aisles are typically only slightly wider than the truck and its load, often in the range of about 5 to 6 feet, while reach truck aisles are wider and counterbalanced forklift aisles wider still. The exact width depends on the truck model, pallet size and the clearances set by the truck and rack manufacturers.
Can regular forklifts be used in a VNA aisle?
No. A counterbalanced forklift or reach truck needs room to turn 90 degrees to face the rack, and a VNA aisle does not provide it. Standard trucks can still work elsewhere in the building, bringing pallets to and from pick-up and drop-off stations at the aisle ends, while the VNA trucks handle storage and retrieval inside the aisles.