we are working on "hotel style" apartments (retirement place), 74 units in this building. each unit has a 90 amp sub-panel. To feed these panels we ran 2-3 w/gnd sub-feeds. Some runs are as far as 350 feet from the meter room.
Anyways, to the point...the foreman had some helpers strapping the cables every 4 feet, the problem is they are doing the three at a time with zip ties and drywall screws!
Next, all the circits i ran in the corridors (12-2 and 12-3 MC Cable), the foreman had me "strap", all in a bundle, with 2 1/2", 2", or 1 1/2" EMT straps.
Mike, I was actually taught that the Romexes had to be separated in order to provide for heat dissipation by a Riverside County inspector. Have you had any inspections yet? (I also cut all the ty-raps off of the wiring inside panels when I find them. They make for a very neat looking job, but when they're all bundled for 24" or more, as mentioned earlier, it becomes a derating problem)
electure: we are actually working in Laguna Niguel right now. we have had an inspection, but only on the first floor of this building. All the sub-feeds are run from the meter room to the third (top) floor and then down to the panels on 3, 2, & 1 floors, so the inspector has not seen this yet.