I've been following this thread from it's inception and once again I'm amazed at the mission creep on TBN.
As one poster wrote undoubtedly some construction worker that weighed more than the roof top tent walked across the joists with no problem.
But then I start seeing the project getting bigger and bigger until it's spanning the width of the building. I'm sure some of you guys have all sorts of free I beams just laying about.
And pretty soon you are building something like this:
from Shield Arc.
But many of us don't have free steel.
To me the way to do it would be first jump up and hang by the joists to see if there is any movement. If it feels solid then lay the plumbing pipe across the joists, measure the joist distance from the floor, hoist the roof top tent up CAREFULLY and measure the change in JOIST height. There may be none if the pipe lays on 4 joists. Then if you want to beef it up fasten uprights at either end of the span.
I've a small shed with a 10 foot wide gambrel roof frame made of 2x4's which I store wood, fencing and other stuff. Well over several hundred pounds. Been there since 1986. No problem.
I've been planning on a similar hoist to lift things like my
chipper
or my bandsaw
.
What I'll probably do is find a 15 foot I beam of sufficient strength and mount it on a pair of lally columns/jack posts I have. I'll attach the columns to uprights that are supporting the roof and beams in the roof to prevent movement.
So OP, think how much mission creep you can do and still get the mission done in a timely manner.