Small items are becoming more and more common, yet shelving is still designed with pallets in mind.

Anyone who runs a small-item e-commerce warehouse has probably experienced this shift: at first, one SKU per box; then, dozens of SKUs per box; and eventually, only a few or a dozen items per SKU. The total number of items isn’t that high, but the variety has multiplied. Looking back at those rows of heavy-duty racks in the warehouse—designed for handling full pallets—it all feels a bit off: a single storage bin is crammed with products from several different suppliers, and the people searching for items have to rely on rummaging, memorizing, and asking others.

I. The bottleneck often isn’t “running out of space,” but rather “slow searching and long walks”

In warehouses with high volume and few SKUs, efficiency comes from moving entire pallets in and out, so shelf heights and aisle widths are designed around forklifts. But when the number of SKUs reaches hundreds or even thousands, and only a few items are picked at a time, the main player in the operation has actually changed: it’s no longer forklifts zipping through aisles, but people pushing pick carts, walking between rows of shelves, and retrieving items from each storage bin one by one.

Consequently, the criteria for evaluation also change. From a forklift’s perspective, the focus is on “Are the aisles wide enough? Are the storage bins deep enough?”; from a person’s perspective, the focus is on “Is this storage bin within arm’s reach?” and “Are the items for the same order scattered across opposite ends of the warehouse?” The former concerns storage efficiency, while the latter concerns walking distance—and a significant portion of a worker’s daily shift is spent walking.

II. Medium-Duty Racking: Placing Storage Bins at a Height Within Reach

The concept behind medium-duty shelving (also known as shelf-type racking or medium-duty shelving) is to return storage to the premise of “manual retrieval.” It uses shelves instead of beams, with the spacing between shelves determined by human retrieval habits. The overall height of the rack is typically kept within the reach of a standing person’s outstretched hand, with a small ladder provided when necessary. There’s no need to climb high or crouch down to rummage through boxes; you can retrieve goods right from the aisle.

For small and medium-sized items, cartons, returnable containers, and accessories, this structure is often more convenient: shelves can hold loose items directly without needing to consolidate them onto full pallets; shelf spacing can be adjusted based on the height of the goods; and a single row of racking can be zoned by SKU, placing fast-moving items closer to the aisle entrance.

III. These Prerequisites Must Be Clearly Considered Before Construction Begins

First, the shelving must carry goods that “people can move.” Medium-duty shelving is generally unsuitable for heavy individual items or goods that require palletized loading and unloading. Forcing such items onto the shelves can easily cause shelf deformation or structural issues with the uprights. Before selecting a model, clearly communicate the individual item weight, the number of items per shelf, and the placement arrangement to the supplier.

Second, the shelf height determines how many tiers can be added. You must account for the warehouse’s clear height, fire sprinklers, lighting fixtures, and utility lines, while also leaving space for people to stand and access the goods; if you stack too high, the top tier will become little more than a decoration. Aisle width should also be determined based on the actual need for order pickers and people to pass each other; if the aisles are too narrow, the space saved will be offset by the inefficiency of walking.

Third, higher storage density isn’t necessarily better. This is a common misconception regarding medium-duty racking—its strengths lie in ease of access and adaptability to a wide variety of items, not in cramming every square meter full. If a warehouse contains both large, full-pallet items and small, loose items, the most prudent approach is to divide the space into zones: design the large-item zone for full-pallet storage and use medium-duty racking in the small-item zone for manual picking, rather than applying a single solution to the entire warehouse.

Fourth, fire lanes and emergency exits must not be blocked by racks or goods—this is a fundamental safety requirement. It is recommended to coordinate the placement of facilities such as sprinklers, smoke detectors, and evacuation signs with the facility management during the planning phase.

IV. Measure the Space First, Then Develop a Plan

When it comes to your own warehouse, the key variables to determine are essentially the same: the approximate number of SKUs, the inventory depth for each SKU, the approximate weight per item, the number of daily picking operations, the width of existing aisles, and the remaining clear height. Without these figures, simply selecting equipment based on catalogs can easily result in a setup that “fits but isn’t practical.”

Shibang Racking begins with an on-site measurement visit: we take precise measurements of the facility, clarify the inventory structure and picking methods, and then produce a layout diagram indicating which areas are designated for full-pallet storage, which areas use medium-duty racking for manual picking, how aisles should be configured, and where picking routes are arranged. Only after the drawings are clear and the installation is feasible do we proceed to the next step—this is far more efficient than providing a quote first and then having to redo the work later.