^Yes, but all the housing projects using containers such as Lot-EK and such use them within a framework.
He said 'non-reinforced', which assumes just stacking one on top of the other. On a big Panamax ship I think they can get stacked 7-8 high, but I'm not sure if the pile then gets strapped down somehow.
Anything over 3 high or so would be subject to wind loading.
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