An extra foot of roof. Sounds minor, changes everything — if someone is going to stand up and work in it through a Bundaberg summer, or you're racking pallets, buy the high cube and don't think about it again.
Two reasons, and only one of them is headroom. The obvious one: if a person is going to stand up and work in it, 2.69m is the difference between a usable space and a stoop. That's why nearly every workshop and packing-shed conversion we supply is a high cube.
The second one is air. Sealed steel in this humidity sweats overnight, and the moisture ends up on whatever you've stored. The extra height gives you room to fit vents high on both ends so air can actually cross the space instead of sitting in it. There's more on that in salt air, steel and the Coral Coast.
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