Mikepier wrote:
I was shopping in Lowes tonight for a basic toilet to replace an old
one we have in a rental. The original one in the rental is 10" rough
when I measured from the flange studs to the wall. Lowes only sells
12" rough-in in stock, however the toilets they had on display I
measured just for curiousity, and most actually measured about 10"
from the flange holes to the back of the tank. So I'm just wondering
why they do this?

Here's a link to a few blurbs about the rough-in measurements, people's
preferences, etc.:

http://www.askmehelpdesk.com/plumbin...5915-last.html

As far as I can tell, different people have different preferences regarding
how far from the wall the tank should end up being. I have seen many setups
where the distance is one or two inches, and the two-inch distance seems a
little strange to me. I would rather see the distance be much smaller,
maybe 1/2-inch, but not have the tank actually touching the wall (so taking
the tank cover off won't involve rubbing it against the wall).

But, given the above discussion link, I think maybe you'll get what you want
by buying one of the 12-inch rough-in toilets you saw. If you take careful
measurements, which you appear to have done, the end result seems like it
would be that the 12-inch toilet you buy will fit well in the space you have
and will end up with the tank close to, or touching, the wall.