Double Deep Racking stores two pallets deep, or four pallets deep in a double entry rack. Double entry racks reduce the aisle to rack ratio but also reduces pallet selectivity, increasing storage density.

50% immediate pallet access provides reasonable stock rotation on a FILO (First In Last Out) basis and makes good use of all available locations. This system is best used when each SKU has several pallets.

The system requires the use of a special reach truck with either dual pantograph or slide fork attachments. Truck lift heights are limited by load to about 9 meters.
Upper levels can be fitted with guide rails to assist forklift drivers in locating pallets; They also help reduce fork truck operator error and accidental impact damage.
Double deep pallet racking

Skecth:
Double deep pallet racking
Modified reach trucks with the ability to stack two pallets deep operating in almost conventional reaches truck aisles store pallets in single entry racks. Back to back racks are four pallets deep. This reduces the aisle to rack ratio but also reduces selectivity, (FILO). Truck lift heights limited by load, to about 9 meters.

Usually the upper levels have front to back rail guides to assist the driver locating the rear pallet at height.

Double deep pallet racking

Advantages
@Storage density increased as rack aisle ratio changes from Selective racking
@50% immediate accessibility with reasonable stock rotation
@Good use of all available locations, typically above 90%
@Safe and secure handling with the bottom pallet usually off-ground
@Ability to use double deep handling equipment for other tasks
@Best used when each SKUhas several pallets