First set the single-cage height: cage height equals the goods stacking height plus handling clearance; too little clearance makes loading and unloading hard, too much wastes space and raises the total stacked height. When loading bagged or boxed goods, also consider the convenience for workers bending to pick and place.
Then consider stacking layers: total stacked height is limited by warehouse floor height, fire safety, and aisle clearance, as well as forklift lift height; the more layers, the higher the requirements on the bottom cage's stacking load capacity, post strength, and floor flatness.
When stacking 3 layers or more, be sure to confirm the stacking load parameters and recommended layer count with the manufacturer; in areas with uneven floors or frequent forklift traffic, lower the stacking height or reinforce the bottom layer to prevent swaying and tipping.
When used with racks, cage height must be less than the rack beam spacing; cages intended for rack storage must also have length and width matching the rack beams to avoid being placed suspended.
Providing on-site floor height, goods height, handling equipment, and stacking requirements together to the manufacturer, letting them issue the size and stacking plan, and verifying by sampling before mass production is the most reliable process.