Questions on Toto Drake specifications

Terry, you seem to be the Toto guru. Can you help me out?

I don’t understand Toto’s specifications.

I replaced a toilet with a Toto Drake CST744S. The included instructions state that the rough-in must be at least 12 inches, which is what I have. The included drawing shows the distance between the wall and the back of the water tank lid should be 3/4-inch. Toto’s web site spec. sheet shows the distance as 1-1/8 inches.

In reality, I ended up with a distance of 2-1/4 inches from the wall to the back of the water tank lid. I contacted Toto and inquired as to the discrepancy. The Toto rep. asked for some mfg. numbers on the water closet, but none were to be found. He then suggested they should replace the water closet.

The replacement has been installed and it measures 2-1/8 inches from the wall to the back of the water tank. (These figures take into account a slight variance in the plumb of the wall and the floor is level.)

This weekend I was in a hotel that had what appeared to be the same toilet, but one that was ADA compliant. (It had a ST743S tank.) It looked very good, as the water tank lid sat very close to the wall, but they used only a 10-5/8 inch rough-in.

My next project is to replace a really old toilet that has a 12-5/8 inch rough-in. I would like to install a Toto Drake CST744S. If I do, must I simply accept a huge space between the wall and the back of the water tank lid or is there a simple fix?

Thanks for the help.

You have discovered what is a somewhat confusing fact about toilets. All that is really standard is that a toilet calling for a 12" rough in will fit a flange that is a true 12" from the finished wall. What is often not specified is how much space will be between the tank and the wall. Some folks have used this to their advantage when their rough-in is shy of the 12" because they can still use a 12" rated toilet. This problem seems to be with all toilets, and will vary from model to model as you discovered. Fortunately, no toilets that I am aware of require more than the distance the toilet specs call for.

Did you measure from the "wall" or from the "floor molding"?

My experience is with the Drake is about 1" behind the tank when it's set at 12" from the "wall".

Terry,

The wall is tiled, with no base molding. The flange studs are 12-1/8 inches from the tile surface. The back of the tank (sans lid) is 2 inches from the tile surface. With the rounded edge on the back of the lid, that 2 inches looks like a really big gap.

The replacement water closet from Toto came from the same supplier as the original water closet. The Toto rep. said that he had heard of units being shipped that were not correctly made and that is why he so quickly shipped a replacement.

Now I'm wondering how I could receive two "defective" units, but no one else has had a similar problem.

Secondly, how can Toto have two different specs (3/4 inch and 1-1/8 inch) for the same product?

Thanks again for your help.