[snic]

I'd like to buy a replacement toilet before pulling out the old one. But I'm not certain about what size rough-in I have. There are two sets of bolts, one at 10.75" from the wall, and the other at 15.5". (I added a quarter inch to the measurements in the picture because the tape measure stops at the tile, not the wall).

I'm guessing the closest set of bolts is the one where the flange is. So I guess the toilet I buy should be designed for a 10" rough-in?

 

[MTN REMODEL LLC]

New to me....but I bet you are right....sure never heard of a 15" roughin toilet.

Is there a hold down bolt/nut on both those holes.

You likely will find only very limited choice in 10's.....there are adjustable offsets for 2" if you can work them in,,,

 

[snic]

Yes, there are nuts on both those bolts (and on the other side of the toilet, too). But the hole in the ceramic is bigger for the one closest to the wall, FWIW. Really odd - I wonder if this is the original toilet from 1957. The tank is enormous, but then I'm used to 1.3 gpf toilets.

This is the 10" I was thinking of replacing it with. I'm partial to Toto toilets as I've installed several and literally never had a problem with them.

https://www.supply.com/toto-drake-1...iece-toilet-cst746cemfg.10-01-cotton/p2550753

 

[miamicuse]

There is another option is you are going to get a Toto toilet.


Some models of Toto toilets support what they call a "Unifit" trapway to accommodate a 10", 12" or 14" rough in.


https://www.totousa.com/filemanager_uploads/product_assets/0GU185_UNFIT_ROUGH_IN_IM.pdf


The same toilet, fitted with a different size Unifit adapter, that looks like this, would accommodate the required rough in.

 

[snic]

Yes, I installed one of those unifits before, when I had a 14" rough in. Unifit models were all Toto had for 14". The problem is that the trapway costs $60 or something ridiculous. The toilet comes with the standard 12" trapway, and if you want 10 or 14, you have to buy another one. (Also you have to install it by drilling holes in the tile floor, which is an extra step I'd prefer to avoid.)