Distribution centres: keeping a store network stocked on a timetable

The handling unit is a case or a layer

Demand from an outlet is rarely for a single item, so picking works in cases, layers or full pallets. That permits powered equipment, deeper storage and higher pick rates per operator than loose-unit work, and it keeps the recorded quantity aligned with the supplier's packaging. It also means the pick face has to be replenished in whole pallets, which turns replenishment into a scheduled activity rather than an interruption.

Route times release the work

Orders are not released when they arrive; they are grouped so that each vehicle's stock is completed shortly before its departure, in reverse drop sequence where the load is built that way. Releasing too early fills the staging lanes and blocks the doors, while releasing too late leaves a driver waiting. Getting this rhythm right is worth more than any single productivity improvement inside the aisles.

Loads have to survive the receiving end

An outlet usually unloads without a forklift, through a back door, into a small stockroom and often with limited staff. Loads are therefore built into roll cages, dollies or pallets that can be moved by hand, sorted by department or aisle so the shop is not forced to sort them, and stacked heavy to light. A depot that optimises only its own picking cost pushes labour into every store it serves.

Storage is a buffer, not the mission

Because stock is passing through rather than accumulating, holding times are short and the instinct is always to shorten them further. Fast-moving lines may be handled with little or no putaway, going straight from the inbound door toward outbound staging. The result is that the depot's true capacity is measured in movements across the doors, not in pallet positions occupied, which is why a full-looking building can still be starved of throughput.

The equipment comes back

Cages, dollies, trays and pallets circulate between depot and outlet, and they represent real capital that is easy to mislay. Loads returning are therefore an operational stream in their own right, needing a place to collect, count, clean and repair the equipment. Sites that neglect it end up buying replacements while their own assets sit in the back rooms of the network.

Frequently asked questions

Why do depots build loads in reverse drop order?

So that the first outlet on the route is nearest the vehicle doors. It removes the need to unload and reload at each stop, cuts standing time on the kerb and reduces the chance of stock being delivered to the wrong site.

Is more storage space the answer when a depot feels congested?

Rarely. Congestion in this format is usually a door and staging problem caused by work being released in the wrong sequence, so adding racking simply converts a flow constraint into a fuller building with the same departure delays.