A height adjustable column for a shipping container building structure. The height adjustable column has an upper sleeve portion, a middle sleeve portion and a lower sleeve. When the column is in the non-extended position the middle sleeve portion is fully slid within the lower and upper sleeve portions and a substantive length of the upper sleeve portion is slid within the lower sleeve portion such that ISO apertures in the middle sleeves are aligned whereby the height of the column is at a reduced height compared to that that of a standard shipping container. When the column is in the extended position locking means on the middle sleeve portion engage and lock with the corresponding slotted apertures on the lower and upper sleeve portions as to support and retain the column at a height equal to or greater than the height of a standard shipping container.