spiral staircase for loft

When you cantilever out you can only go 1/3rd the total length of the beam. So if it sticks out 5' it needs to be sistered back in 10'. If you cant do that then it's time for posts.

Also not sure if you've ever used a spiral staircase but they are dangerous to go down...

I didn't read all the replys yo not sure if this helps.