Experts suggest that your operation needs a walk-in when its refrigeration needs exceed 80 cubic feet, or if you serve more than 250 meals per day. Once again, you'll need to determine how much you need to store, what sizes of containers the storage space must accommodate, and the maximum quantity of goods you'll want to have on hand. The only way to use walk-in space wisely is to equip it with shelves, organized in sections. Exactly how much square footage do you need? The easiest formula is to calculate 1 to 1.5 cubic feet of walk-in storage for every meal you serve per day. Another basic calculation: Take the total number of linear feet of shelving you've decided you will need (A), and divide it by the number of shelves (B) you can put in each section.