An open-air platform is an elevated steel structure with dock positions and a connected yard ramp for equipment access. It stands exposed to the elements and is the right configuration for operations where weather protection is not a requirement.

An enclosed platform adds walls, a roof, and rollup doors with dock seals. Depending on the application, the enclosure can include a man door, interior lighting, dusk-to-dawn solar exterior lighting, stairs or a ramp for personnel access, and heat or air conditioning. A lean-to roofline can be specified for precipitation runoff. The enclosed platform is the right configuration for temperature-sensitive freight, year-round operations in variable climates, or any application where weather exposure is an operational or safety concern.
Both configurations are portable. Neither is a building.