Having worked for more than a couple of decades as a DC designer / layout specialist, my most common task has been to fit rack and aisle layouts into buildings of all shapes and sizes. The most frequently requested pallet racking layouts feature pure single-deep racking with pallets handled by reach trucks on the 40” face. Quite often a few runs of double-deep (or 2-deep pushback) racks are added to handle faster moving products.
Whether layouts are for existing buildings or new facilities, the spacing of building columns is always an issue. Certainly, the best set-up is for all the columns to land in the flue spaces between back-to-back runs of rack where they won’t interfere with pallet storage or mobile equipment.
As an example, 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” (rack face to rack face) as shown in figure 1. This layout uses 42” deep racks, so standard 40” x 48” pallets 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. Tighter aisles result in slower loading and unloading of racks. In larger spaces, extra wide aisles have a significant negative effect on storage capacity.
Building column spans, center-to-center, that range from 38 feet to 40 feet are among the most suitable for pure single-deep layouts. They are well spaced for pallet racking layouts that create appropriate aisle widths and don’t result in columns lost pallet spaces.
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’.