No, not in normal circumstances. God’s gravity anchors them solidly to God’s earth. Our portable buildings are so heavy and so sturdy that they will not blow over–unless a tornado hits them. However, some city codes (Stillwater, for example) require anchoring portable buildings. (It’s your responsibility to check that out.) So we offer an anchoring package for our buildings, and we recommend that you consider anchors if you buy a portable cabin or office.
When we anchor a building, we use auger-style earth anchors (“mobile home anchors”)–two on a very small building, 4 on most buildings, but 6 or more on our largest buildings. We screw these anchors screw into the ground and “lag” them to the skids of the building. In addition, we use steel “strong ties” to secure the runners to the floor joists. No one wants to crawl out of his storm shelter after a tornado and see 4 skids securely anchored to the ground–and the building dumped in the neighbor’s field.