The normal distance to the center of the toilet flange/drain is 12" from the finished rear wall.

12" is "standard" but other distances are possible depending on the setup. As noted above, 12" is from the finished wall, not the stud. If you are drywalling, you will need to add in the thickness of that to the 12" if you are measuring from the stud. eg 1/2" drywall + 12" = 12 1/2" from the stud wall for the center of the flange.

There is not a code standard for the distance from the back wall because the length of the offset is determined by the design of the toilet you intend to install.

The industry standard for the back offset is 12" from the finished wall however toilets are also made with 10" and 14" back sets. You will need to check the installation instruction for the model of toilet you choose.

In addition to the back set, the codes require that you have a minimum side clarance of 15" from the center of the flange to adjacent wall, fixture or appurtenance.

In addition;

The IRC (international Residential Code) requires a minimal frontal clearance of 21" measured from the front lip of the bowl to any wall fixture or appurtenance.

The UPC (Uniform Plumbing Code) requires a 24" frontal clearance.

Lazypup,

You mention the minimum 21' clearance from the front lip of the bowl. Can you translate that into a "rule of thumb" minimum room dimension, and perhaps also a "comfortable" dimension when building an opposing wall? Seems like a 48" total room dimension would usually work for a standard bowl, yet 5' is the visually comfortable minimum. Sound right?

I'm looking at a basement build-out that has the drain rough-in in the slab (from the original construction 8 yrs ago), but basement plans are unavailable, so it's anybody's guess what they were thinking. It is "assumed" by the owner and original design architect to be a two part bathroom, but, since the toilet is (assumed to be) aligned toward the second room tub, it seems there's not enough clearance for a toilet, partition, and then tub on the far side (drain is on far end in that room. Hope that makes some sense.

The normal distance between the wall and the toilet is between 10"-14", or may be determined according to the industry standards.TPH supply is the manufacturer who does well while setuping my bathroom and toilet wall and i no need to care about. Thanks to tph supply.

Here is a link that might be useful: Toilet Partitions