I have been working for more than a couple of decades as a DC designer / layout specialist. During that time, my most common task has been to fit rack and aisle layouts into buildings of all shapes and sizes. Experience has shown me that the most frequently requested pallet racking layouts feature pure single-deep racking with pallets handled by reach trucks on a 40” face. I have also noticed that, quite often, a few runs of double-deep (or 2-deep pushback) racks are added to the layout to handle faster moving products.
Whether layouts are for existing buildings or new facilities, the spacing of building columns is always a concern during design. Certainly, the best set-up is for every column to land in the flue spaces between back-to-back runs of racking so that they won’t interfere with pallet storage or mobile equipment.
As shown in figure 1, a building with columns spaced on 40 foot centers will result in a pure single-deep pallet racking layout with consistent aisle widths of 11’-7” (from rack face to rack face). This layout uses 42” deep racks. Standard 40” x 48” pallets will therefore overhang the load beams by 3” front and back. Taking this into account, the aisle widths pallet to pallet are 11’-1”. Aisle widths are to some extent a matter of preference. Keep in mind, however, that tighter aisles will result in slower loading and unloading of racks. For that reason, we recommend avoiding widths of 9’’ or less. Meanwhile, in larger spaces, we advise our clients to avoid opting for extra wide aisles as those will have a negative, and possibly costly impact on storage capacity.
When column spacing is not ideal, it poses additional challenges for the design of a new layout. At LIDD, we have the resources and experience to help you overcome these challenges. In these cases, just as with more ideal situations, we will assist you in improving your warehouse’s configuration so that it may meet your true capacity needs and maximize your ROI.
But what to do if your column span isn’t the ideal 40’? Read Steve’s next post on handling racking layouts in warehouses that have aisles wider than 40’.