12" rough-in toilets actually measure 10"?

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?
Reply to
Mikepier
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To allow for varying wall thicknesses, for one reason, but mainly its because a little short is a lot better than a little long.

R
Reply to
RicodJour

Until someone leans back on it anyway.

Reply to
Molly Brown

Well, good news for me is at least I don't have to special order a 10" bowl. It looks as though I can buy a 12" bowl off the shelf as it will fit.

Reply to
Mikepier

??? Toilet tank is not supposed to touch the wall. If they can 'lean back' and make the toilet move, either the floor and drain line assembly are rotted out, or the tank was not secured to the bowl properly.

Reply to
aemeijers

Uh, make sure the back of the tank, including the lid, won't hit the wall, before you decide against the 'close fit' model. On mine, they extend several inches back past the base.

Reply to
aemeijers

Why do they do what? Give accurate dimensions? The rough-in dimension is the distance from the *centerline* of the opening to the wall. Since the opening is 4" in diameter, hence 2" in radius, the distance from the *edge* of the opening to the back of the tank is *supposed* to be a bit less than 10" for a

12" rough-in.
Reply to
Doug Miller

the tanks are mounted on rubber bushing and a big rubber gasket. They do move when leaned on. And thus so, should be positioned so the lid touches the wall. I'd break mine right off if it didn't.

Reply to
Steve Barker

he'll find out soon enough. If in fact his bolts are centered on the flange, and IF in fact they are 10" from the wall, then he's probably NOT gonna be installing a standard 12" setback toilet.

Reply to
Steve Barker

Good pick up. I skipped over the part where he was measuring from the flange bolts and not the centerline.

R
Reply to
RicodJour

Every tank I have ever seen has resilient mounts and will move relative to the base if someone leans against it.

Reply to
George

Sorry, Steve, just not so. Commercial toilets don't even have tanks. No toilets depend on the tank leaning against the wall. The floor/wall connection needs to be solid on its own. The rubber or wax gasket is for a water and gas tight seal, not for supporting or holding the toilet. Vitreous in contact with the floor or shimmed while being held down by bolts that are well anchored into the floor or attached to the floor flange if it is rigidly mounted.

Reply to
DanG

Okay, they can move a little. Emphasis on 'little', like enough to avoid fracturing china around the bolt holes when you bump it or flush it. But it still isn't a frigging lazyboy recliner. I've never seen a properly installed modern toilet where the tank or lid touched the wall in normal usage. You want air flowing back there, to keep the wall condensation-free.

Not to mention, leaning back is NOT the recommended 'fecal position' posture for the process. The geometry is all wrong. Rodin had it right with his 'The Thinker' statue. Anybody still sell those joke paperweights with that sculpture sitting on the john? Always wanted one of those.

Reply to
aemeijers

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

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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.

Reply to
RogerT

I am of the opinion without any proof that this RO measurement has evolved a bit over the years. Most likely as a result of the smaller tanks using 1.6 gal.

35 years ago if you were installing a new flange we measured out from the studs 12-1/2". Then about 20 years ago that was suddenly leaving way too much room behind the tank.

So let's surmise that it is now a 12" RO from the studs, add 1/2" of drywall, 5/8" of base and 1/2" of shoe base and you depending on what you measured, where and how well you could easily be 10-10-1/2" from the shoe base to the center of the flange.

The only way you will ever know for sure is buy it, open carefully and dry fit the thing.

I just went in and measure my Mansfield. The measurement is 11-1/2" from the shoe base to bolts. The Mansfield unlike many cheaper BORG units has a tapered back so that it is closer to wall at the top than it is at the bottom. Even with that I have an inch between the tank lid and the wall. Most of the BORG units have a straight back on the tank. Over the years I have routinely added a small scrap of 2x4 to the wall behind the tank to prevent tenants from breaking something when the feel the need to recline on the john.

I have a hunch that the $80 jonnie in box from Lowes will work just fine for you though you may choose to upgrade the seat.

Reply to
Colbyt

You either didn't tighten the bolts enough or you're pushing REALLY hard. The tank should probably have a small amount of give to keep from breaking things, but should definitely NOT be touching the wall. Many bathroom walls are made of drywall which would be damaged by this, and you sure don't want your porcelain tank or lid slamming against a tile wall when you flop down.

I'm trying to picture the framer, the drywaller and the plumber that built your house all using their precision t-squares to make sure the toilet flange is mounted in exactly the right place so that a particular model of toilet will sit exactly touching the wall when everything is finished...

Nope, still having trouble picturing it, so I'm coming to the conclusion that that would be a bad design... :)

Reply to
Larry Fishel

who said anythin' about a commercial toilet?

Reply to
Steve Barker

The toilets that you=92ve seen must have been used by angelic people. With some of the people that I have had to deal with I had to custom cut a piece of wood and screw it on the wall behind the tank to keep them from breaking the tank or at least causing it to leak when those gaskets become dry and brittle . Especially those new thin China ones. I=92ve never seen a wall become damaged by condensation from a tank without all the bathroom walls being damaged first, but those bathrooms didn=92t have a vent fan in the first place. In older houses I have seen it where you couldn=92t stick a sheet of paper between the toilet and the back wall, a tribute to those old world plumbers who took the time to do it right.

Reply to
Molly Brown

Might I recommend 'vandal proof' (AKA prison) toilets? Sounds like some of your customer base might be happier with facilities out back in a small dedicated building.

Perhaps some of those old houses originally had the high-mount tanks that were actually hung on the wall.

Reply to
aemeijers

Errm...the flange bolts _are_ on the centerline. At least they asre if those are the bolts used to fasten down the toilet.

Harry K

Reply to
Harry K

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