Regarding Uhauls, I was under the impression they were more like 10-11', but I'm not sure where I got that number. But also, the deck height seemed like it was less than ~3' in most, which already left about another ~3' of height in the attic as a starting point...
After
double-checkling, here's what I got:
- 14' Uhauls
Top to ground height: 11' (2007)
Box deck height: 32" (2007)
Box inside height: 7' 2" (2007)
- 17' Uhauls
Box outside height: 11' (2006)
Box deck height: 32"
Box inside height: 7' 2" (2006)
- 24' Uhauls
Outside height: 11' (2000)
No deck height measurement
Inside height: 7' 1'' (2000)
It looks like they are only 11' tall (the 14' says it's 11' "top to ground"), which means--assuming it's structurally safe--it is feasible to add 2' to the height. It also looks like the deck height in most of them will be close to 32", meaning that before insulation or increasing the height I'd probably have ~52" of height for my attic bed.