Selective rack
Also called: selective pallet racking, single-deep rack, standard pallet rack
Selective rack is the most common pallet racking: one pallet deep from each aisle, so any pallet can be picked without moving another. The pallet rests on a front and rear beam and spans the gap between them.
In depth: Pallet racking and deflection: rack spans, direction and sag limits
Selective racking gives up floor density for access. Every pallet position faces an aisle. A double-deep variant stores two pallets per side and needs a reach truck with extending forks.
How the pallet sits
In North America, a 48 × 40 in (1219 × 1016 mm) pallet usually goes in with its 40 in face on the beams and its 48 in length running from the front beam to the rear beam. The pallet is then racked across its length: the stringers or stringerboards span the gap. The frame depth is typically set a few inches shorter than the pallet so the pallet overhangs each beam slightly. The rack designer sets the exact frame depth.
What it needs from the pallet
| Requirement | Why |
|---|---|
| Racking load rating at the actual span | The pallet spans open air |
| Deflection within limits | Sagging pallets catch on beams during retrieval |
| Sound lead boards and ends | They rest on the beams and take fork impacts |
| Consistent dimensions | Pallets must bear on both beams |
Wire decking or pallet supports change the support condition and can raise effective capacity. State them on a spec if they are present.
On a spec sheet or RFQ
"Selective rack, racked across length, 2 beam support, span 44 in" is the kind of line a manufacturer can design to. Add the load duration and the deflection limit.
Common confusions
A pallet placed turned (48 in face on the beams) in a selective rack is racked across width, and its capacity can be quite different.
Related
- GlossaryWhat is pallet racking?Pallet racking is a steel storage structure of upright frames and horizontal beams that holds loaded pallets in levels above the floor. The pallet usually spans the gap between two beams, so its racking load rating, not its floor rating, governs.
- GlossaryRack beamA rack beam is the horizontal steel member that spans between upright frames in pallet racking and carries the pallets. The distance between the front and rear beams sets the pallet's unsupported span.
- GlossaryRacked across lengthRacked across length is a support condition where the rack beams support the pallet's two ends and the pallet's length spans the open gap. On a stringer pallet the stringers carry the load across the span.
- GuidesPallet racking and deflection: rack spans, direction and sag limitsIn a rack a pallet spans between two beams with nothing underneath, so it bends. Racked across the length (stringers span about 40 to 44 in on a 48 in pallet) is usually stiffer than across the width (deckboards span about 36 in). Common deflection limits are about 2% of span, or 0.5 in or less for automated storage.
- GlossaryRacking loadRacking load is the weight a pallet can safely carry while it spans the gap between rack beams with no support underneath. It is usually the lowest of a pallet's ratings and depends on the span, the direction racked and the number of beams.
More in Handling and storage
- GlossaryAutomated storageAutomated storage, often called AS/RS (automated storage and retrieval system), stores and retrieves pallets with stacker cranes, shuttles and conveyors instead of forklift drivers. It needs pallets with tight dimensional tolerances, low deflection (often 0.5 in, 13 mm, or less) and sound bottom decks.
- GlossaryBlock stackingBlock stacking is storing unit loads directly on top of one another on the warehouse floor, in rows and columns, with no racking. The bottom pallet and the packaging carry the whole stack, so static load and box compression strength limit the height.
- GlossaryConveyorA pallet conveyor moves loaded pallets on driven rollers or chains instead of a forklift. The pallet's bottom deck is the running surface, so the orientation of bottom boards, flatness, deflection and condition decide whether it runs reliably.
- GlossaryDrive-in rackA drive-in rack is high-density racking where the forklift drives into a lane and places pallets many deep on continuous rails along each side. The pallet is supported only along two edges, so its capacity across the unsupported direction governs.
- GlossaryEdge protectorAn edge protector, or corner board, is an L-shaped strip of laminated paperboard, plastic or other material placed on the vertical or top edges of a unit load. It spreads strapping and stretch wrap pressure, protects case corners, and can add vertical stacking strength.
- GlossaryFork tinesFork tines are the two steel arms on a forklift or pallet jack that slide into a pallet's openings to lift it. Their width, thickness, length and spacing set the minimum size of the pallet's openings and affect its dynamic load rating.
Last reviewed 2026-09-24. 272 words.