I hung below my desk from a loft bed frame. Even the diagonal was a bit short, but I was close to the ground. You might be able to pick up a deal on a loft bed, (like a bunk bed with the two top bits). Hang it from the corners, even then the sag will probably be such that you won't need a ladder. Skin the hammock or tie it back to get it out of the way.
my hammock gear weights total: 2430g (~86oz)
Winter: total 2521 (~89oz)
(see my profile for detailed weights)
gram counter, not gram weenie!