Since the pallet rack footplate stabilizes the pallet rack in the first place, it stands to reason that a larger footplate would offer more stability. A major reason to use a bigger footplate is in seismic applications. In certain geographical locations there could be more movement so a larger footplate would support your system and is often required to get a permit. In these cases the footplate would have to be welded to the column instead of bolted. The footplate size can depend of the ground rating as well. If the slab that the pallet rack is sitting on is not to a certain thickness and/or rating, the footplate must be larger to support the pallet racking. If there is reinforcement on the upright (two columns put together), the footplate would need to be larger. In general, a larger footplate provides more stability and support and increases the capacity of the pallet rack. In certain seismic situations, it is simply much safer and it’s often required to have a bigger footplate.