In 2 story homes I wire, I routinely run a 1" EMT to the attic and terminate in a 12x12x6 pull box for the 2nd floor circuits. When I do this I mount the pull box in a central part of the attic where there is the most headroom and mount it on 24" 2x4 risors/plywood. This not only makes it easy to find in the future, it also keeps anyone from having to lay in cellulose to access it.
