New Toilet Tank right against wall

Old 02-25-21, 02:23 PM
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New Toilet Tank right against wall

My house was built in 1974 and the old toilet (from 1974) had a 1/2 inch space between the toilet tank and wall. The bathroom has a 12" rough-in that I measured from the wall to the center of the toilet flange (where the toilet bolts are located).
I just installed a new Kohler toilet with 12" rough-in but the tank rubs against the wall with no space.

Please advise feedback to correct my issue.


Last edited by kensington; 02-25-21 at 02:31 PM. Reason: title needs to be changed from bowl to tank
Old 02-25-21, 07:31 PM
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'tank rubs against the wall with no space'
are you saying that you don't have room to put the lid on the tank? or the lid is against the wall? you may not have installed the toilet level, having the wax ring squished at the back. Did you try grabbing the toilet an wiggling it to lean it forward a bit to seat level on the wax ring?
Old 02-26-21, 05:00 AM
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Not all toilets are the same size. Even among 12" rough in toilets I've seen some touch the wall while others sit an inch or more away. Part of it is the toilets dimensions. Then there is some leeway when bolting the toilet down. And, depending on how you have the tank tightened it can sometimes have a lean.
Old 02-26-21, 05:02 AM
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I would say that the toilet tank resting against the wall is itself a non-problem provided the spud washer (center seal to the bowl) does not leak and the tank does not rock back and forth on the tank to bowl nuts.

The bowl should be or should have been tested for no rocking back and forth on the floor and the bottom of the bowl not touching the flange prior to installation with the wax ring.
Old 02-27-21, 08:39 AM
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In addition to what everyone else has said, I would use a level and put it on the tank lid and check for level in different directions, and also do the same with the toilet bowl.

I think I had a similar problem a long time ago, and I think it had something to do with me not making sure everything was level. I think maybe I didn’t have the tank fastened to the bowl properly ? – but I just can’t remember. But maybe using a level would give you a hint.

(it's all vague, but I think one time I was afraid to tighten the tank to the bowl as much as was actually needed. I think I was afraid of cracking the tank and didn't tighten it down enough.(as P mentioned in post #3) I know you have to be very careful about that..Maybe that's the time the tank seemed too close to the wall. Just not sure.)
Old 02-27-21, 08:49 AM
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I have a similar problem with one of my toilets where the tank leans a little in the opposite direction, towards the bowl. The problem there is for guys when we lift the seat it is almost straight up and down and if not done properly it will come slamming back down on the bowl. Quite annoying.

It is the fact that when I put the tank on it was not level as others have indicated. It does not leak and I tend to leave unleaking toilets lie and I am used the the seat issue so it almost never happens to me. That said, if it started leaking tomorrow I probably would not get as upset as I would with another toilet because I would then fix both problems at the same time.

By the way, it has worked like this for over 10 years now with no water leaks...and I now know how not to install a toilet tank on a toilet. Win Win.
Old 02-27-21, 04:05 PM
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in my post above, I installed a new Kohler toilet 2 yrs ago on a new 12" ctr hole and I just looked at it and the back of the toilet does lean against the wall. The lid fits on top and doesn't overlap at the back like older toilets I've owned. No complaints on mine.

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