Recently moved into a new house and over time I’ve taken notice that the water level in the bowl of all 3 toilets (same Kohler model) drop. Initially I assumed it was just matching the water level in the trap; however, all 3 level drop to different depths. One upstairs drops about .25”, the other upstairs drops about 1” and the one in the basement drops about 2”. Once each drops to the mentioned levels they seem to stabilize. I’ve read about a couple different possibilities, but would appreciate hearing what you all think too.
Toilet bowl water drops
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WJcandee
Wise One
The level that each drops to is likely their "settle level". The reason you are seeing a drop is that the fill valve for each overfills the bowl a bit when the tank refills (i.e. the bowl refill percentage is a bit too high given the level to which the tank refills and the level at which the flapper closes; put another way, the bowl refill percentage is a bit too high given the time the fill valve runs to refill the tank). Extra refill water will just dribble over the weir in the trapway until the bowl reaches the settle level (whereas a full flush will fill the trapway and cause a siphon which evacuates the bowl).
Even if all your toilets are the exact-same model, and you're telling us that the water spot in each is a slightly-different size, this can sometimes be affected by differences in molding of the toilet and/or the front-to-back tilt of the toilet. A toilet tilted back will have a lower settle-level whereas a toilet tilted forward will have a higher one. Level, of course, is best.
There's also a possibility that flushing a toilet mounted back-to-back with another causes a little splashing in the piping which can siphon the opposite bowl a bit. But if this happens every time, it is, similar to what you thought, likely just dribbling over the weir until the bowl level reaches its settle-level.
This isn't really anything you need to do anything about if you're happy with the way the toilet works. If you are worried about the water wasted, get something like a Korky MaxPerformance 528MP fill valve, and adjust the bowl refill percentage with the little knob on the refill hose of that valve that does so.
Even if all your toilets are the exact-same model, and you're telling us that the water spot in each is a slightly-different size, this can sometimes be affected by differences in molding of the toilet and/or the front-to-back tilt of the toilet. A toilet tilted back will have a lower settle-level whereas a toilet tilted forward will have a higher one. Level, of course, is best.
There's also a possibility that flushing a toilet mounted back-to-back with another causes a little splashing in the piping which can siphon the opposite bowl a bit. But if this happens every time, it is, similar to what you thought, likely just dribbling over the weir until the bowl level reaches its settle-level.
This isn't really anything you need to do anything about if you're happy with the way the toilet works. If you are worried about the water wasted, get something like a Korky MaxPerformance 528MP fill valve, and adjust the bowl refill percentage with the little knob on the refill hose of that valve that does so.
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LLigetfa
DIYer, not in the trades
Another thing to consider is air pressure changes. Some bathrooms are small with few places for air to exit so opening/closing a door can affect the water level in the toilet. You might need to enlist a helper to open and close the door while you watch the level. It is also possible for wind to affect the pressure in the stack vent.
Great information thanks!The level that each drops to is likely their "settle level". The reason you are seeing a drop is that the fill valve for each overfills the bowl a bit when the tank refills (i.e. the bowl refill percentage is a bit too high given the level to which the tank refills and the level at which the flapper closes; put another way, the bowl refill percentage is a bit too high given the time the fill valve runs to refill the tank). Extra refill water will just dribble over the weir in the trapway until the bowl reaches the settle level (whereas a full flush will fill the trapway and cause a siphon which evacuates the bowl).
Even if all your toilets are the exact-same model, and you're telling us that the water spot in each is a slightly-different size, this can sometimes be affected by differences in molding of the toilet and/or the front-to-back tilt of the toilet. A toilet tilted back will have a lower settle-level whereas a toilet tilted forward will have a higher one. Level, of course, is best.
There's also a possibility that flushing a toilet mounted back-to-back with another causes a little splashing in the piping which can siphon the opposite bowl a bit. But if this happens every time, it is, similar to what you thought, likely just dribbling over the weir until the bowl level reaches its settle-level.
This isn't really anything you need to do anything about if you're happy with the way the toilet works. If you are worried about the water wasted, get something like a Korky MaxPerformance 528MP fill valve, and adjust the bowl refill percentage with the little knob on the refill hose of that valve that does so.
I will take a look at this as well. Appreciate it!
Jadnashua
Retired Defense Industry Engineer xxx
Get out a level and compare how level the rim is (front-back) on the three toilets. Once you flush a toilet, the bowl tends to get fill right to the top of the weir, and any excess goes down the drain, giving any individual toilet a maximum water depth. The only refill things that affect that height are the actual height of the weir, how level the bowl is (it might be tipping backwards, which would limit how full it can get), or the fact that the fill valve is not calibrated properly so the bowl actually fills.
The other things such as air pressure, siphoning, etc., would affect the toilet after the flush and fill, not immediately at the end.
Even if they toilets are all the same model, making them out of clay is still a bit crude...there will be variations from one to the other. Toto's production technique is a bit more consistent. Most others still use a technique that hasn't changed in probably 100-years or so and is more hands on, leading to more variability between units. That's one reason why dimensions are listed as nominal...they do vary.
The other things such as air pressure, siphoning, etc., would affect the toilet after the flush and fill, not immediately at the end.
Even if they toilets are all the same model, making them out of clay is still a bit crude...there will be variations from one to the other. Toto's production technique is a bit more consistent. Most others still use a technique that hasn't changed in probably 100-years or so and is more hands on, leading to more variability between units. That's one reason why dimensions are listed as nominal...they do vary.
I took a look and there appears to be slight variation front/back, but strangely more variation left/right. It’s also worth noting the dropping water is only noticeable on the left side of the bowl consistently across all. I included a picture of the more drastic one.
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WorthFlorida
6th clinical trail chemotherapy 5/15/24
Check the floor level, left to right then the toilet at the bowl rim. The bowl rims needs to be almost dead on. If they all look good then it could be a bad batch of bowls from Kohler. Check with the builder or call Kohler. They should be replaced.
When bowls are made, the top rim part is attached to the bottom bowl part with a liquid to paste clay, the same material as the molded parts. Then it is fired to come one piece and they shrink an incredible amount. One thing for sure, water is always level. Either the bowl is not level or a bad mold was used.
https://www.google.com/search?q=level+bubble+lines&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari
When the bubble is centered between the inside pair, it indicates level. But when it touches one of the outer lines, it means the level is pitched at a 2-percent grade (about ¼ inch per foot of run), the slope required for waste lines, sidewalks, and rain gutters to drain properly.
When bowls are made, the top rim part is attached to the bottom bowl part with a liquid to paste clay, the same material as the molded parts. Then it is fired to come one piece and they shrink an incredible amount. One thing for sure, water is always level. Either the bowl is not level or a bad mold was used.
https://www.google.com/search?q=level+bubble+lines&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari
When the bubble is centered between the inside pair, it indicates level. But when it touches one of the outer lines, it means the level is pitched at a 2-percent grade (about ¼ inch per foot of run), the slope required for waste lines, sidewalks, and rain gutters to drain properly.
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So I got home today and took a closer inspection and am baffled. I’ve included pictures below of the basement toilet. It’s completely flush with the floor on one side and a little over .25” off the other... I also checked the floor with a level and both are near the same at least for the portions that are accessible next to the toilet; however, I honestly doubt the floor under the toilet and not visible would be that drastically different. I’ll try reaching out to builder, but in meantime does anyone have a clue why this was done or what would have forced them to install it as such? I also looked to see if sitting on it closed the gap between the floor and toilet, but it didn’t seem to budge.
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WJcandee
Wise One
Well in the one photo you can clearly see wooden shims under the side with the gap between floor and toilet. Plumbers do that when the bowl rocks on the floor. (Terry likes the plastic shims from Home Depot, but lots of people use the wood ones.) The rocking can be the result of many things. Most toilets, because they (as Jim points out) are clay that shrinks dramatically when fired in a kiln, have very-slight imperfections; some manufacturers are tighter on what they release to sell than are others. Kohler is a reputable brand, so it is not likely primarily an issue with the porcelain (although it might be). Are these "builder-grade" Kohlers, or did you specify a particular Kohler model? It can make a difference (although not to say that it has made a difference here).
It looks like the floor slopes somewhat to the right to begin with, based on the photo of your level, then the builder added shims on the left side of the toilet to eliminate rocking when they dry-fit it. By shimming it to the right, on top of the lean of the floor to begin with, your water spot has shifted to a place that is pretty darn unsightly.
Candidly, just from an appearance perspective, that's the worst I have ever seen. And it's probably a non-plumber job, insofar as any real plumber I know who has a hint of pride would have seen that, pulled out a level, and in 5 seconds realized that the weird water spot was the result of shimming on the left combined with a floor slope to the right. If the purpose of the shim is to prevent rocking, as it should be, then if the toilet was shimmed from the other side, the shim would compensate for, rather than exacerbate, the floor lean. They could have given you a pretty-close-to-perfectly-centered water spot, but instead left it like that and went and had a smoke.
For what it's worth, I am a little troubled by the shim that appears to be inserted at about 7 o'clock as you look top-down at the toilet. The better practice is to eliminate front-to-back rocking (which a shim positioned there would seem to be an attempt to do), by "pinning" the toilet forward with a shim or two at the back. Tilting the toilet forward raises the height of the weir a little, leading to a little-larger water spot, whereas tilting the toilet backwards lowers the height of the weir a little, leading to a little-smaller water spot. Of course, for performance to specification, as level as possible is best.
The pictures of this one toilet suggest to me that the difference in your water spot size among three "identical" toilets may well be primarily the result of how the toilets were shimmed upon installation. However, given that someone looked at that water spot, shrugged, and moved on, I have no confidence that they checked that the toilet was filling properly, either. So I would still do the easy checking that I mentioned in my first post.
BTW, WorthFlorida well-stated some good information on toilet bowl construction and what to look at with your level and what it means. It was helpful in looking at your situation.
If this is a newly-built house, which it sounds like from your reference to your builder (as opposed to a house that's "new" in the sense of being new to you), this should have been a punch list item, and should be corrected at no cost to you.
Good luck, and let us know how it goes. Resetting the three toilets properly should make a significant difference. It's not rocket science; getting the bowl positioned properly under the pool of water in the bowl is actually pretty-easy to do if one knows what to do and actually cares.
It looks like the floor slopes somewhat to the right to begin with, based on the photo of your level, then the builder added shims on the left side of the toilet to eliminate rocking when they dry-fit it. By shimming it to the right, on top of the lean of the floor to begin with, your water spot has shifted to a place that is pretty darn unsightly.
Candidly, just from an appearance perspective, that's the worst I have ever seen. And it's probably a non-plumber job, insofar as any real plumber I know who has a hint of pride would have seen that, pulled out a level, and in 5 seconds realized that the weird water spot was the result of shimming on the left combined with a floor slope to the right. If the purpose of the shim is to prevent rocking, as it should be, then if the toilet was shimmed from the other side, the shim would compensate for, rather than exacerbate, the floor lean. They could have given you a pretty-close-to-perfectly-centered water spot, but instead left it like that and went and had a smoke.
For what it's worth, I am a little troubled by the shim that appears to be inserted at about 7 o'clock as you look top-down at the toilet. The better practice is to eliminate front-to-back rocking (which a shim positioned there would seem to be an attempt to do), by "pinning" the toilet forward with a shim or two at the back. Tilting the toilet forward raises the height of the weir a little, leading to a little-larger water spot, whereas tilting the toilet backwards lowers the height of the weir a little, leading to a little-smaller water spot. Of course, for performance to specification, as level as possible is best.
The pictures of this one toilet suggest to me that the difference in your water spot size among three "identical" toilets may well be primarily the result of how the toilets were shimmed upon installation. However, given that someone looked at that water spot, shrugged, and moved on, I have no confidence that they checked that the toilet was filling properly, either. So I would still do the easy checking that I mentioned in my first post.
BTW, WorthFlorida well-stated some good information on toilet bowl construction and what to look at with your level and what it means. It was helpful in looking at your situation.
If this is a newly-built house, which it sounds like from your reference to your builder (as opposed to a house that's "new" in the sense of being new to you), this should have been a punch list item, and should be corrected at no cost to you.
Good luck, and let us know how it goes. Resetting the three toilets properly should make a significant difference. It's not rocket science; getting the bowl positioned properly under the pool of water in the bowl is actually pretty-easy to do if one knows what to do and actually cares.
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WorthFlorida
6th clinical trail chemotherapy 5/15/24
Really need to check the level at the bowl rim. I had a home with one toilet about the same gap you show. They should be nylon shims since wood will slowly rot away. With my situation I even replaced the tile to get it flush and level and I still could not get the gap to close. I might have had a uneven Kohler bowl. I used nylon shims and use grout to fill the gap. Put plenty under it for when it drys it will take some of the weight and it does look better than a big glob of caulking. If you don’t fill the gap liquids will settle under the bowl then odors will start.
I just had a plumber do some work for me remodeling the second floor main bath. He put a bead of grout on the floor tile at where the bowl edge touches the floor. Then he placed the bowl on it and pushed it down, just like a wax ring. Checked the level and snug down the bolts and wiped away the excess grout. Another plumber did our first floor master bath and used grout after setting in the bowl. First floor is concrete, second floor wood. Some guys all they’ll use is caulking but caulking eventually pulls away from the porcelain and once stained of urine, you need to cut It out and replaceit. With grout I spray it with a bathroom cleaner or soak it with a cleaner that contains bleach.
I just had a plumber do some work for me remodeling the second floor main bath. He put a bead of grout on the floor tile at where the bowl edge touches the floor. Then he placed the bowl on it and pushed it down, just like a wax ring. Checked the level and snug down the bolts and wiped away the excess grout. Another plumber did our first floor master bath and used grout after setting in the bowl. First floor is concrete, second floor wood. Some guys all they’ll use is caulking but caulking eventually pulls away from the porcelain and once stained of urine, you need to cut It out and replaceit. With grout I spray it with a bathroom cleaner or soak it with a cleaner that contains bleach.
Jadnashua
Retired Defense Industry Engineer xxx
Especially if these are on a slab, they may not have paid attention to keeping the riser plumb, and the reason the toilet needed to be shimmed like that is that the flange is not level and the high side is preventing the toilet from sitting level. To keep it from rocking, whether the flange is in decent shape or not, a good proportion of installs do require at least a thin shim. If the flange is not level, it can sometimes be hard to get a good wax seal since there may be no room for wax on the high side.
Personally, I tend to use coins...have some in my pocket and are often cheaper than running to the store and buying a pack. Have worked well for me. If you're cute about it, you can get some with the mint mark the current year, so when they tear it apart the next time, they'll have an idea how old it is!
Personally, I tend to use coins...have some in my pocket and are often cheaper than running to the store and buying a pack. Have worked well for me. If you're cute about it, you can get some with the mint mark the current year, so when they tear it apart the next time, they'll have an idea how old it is!
Thank you all for the comments, feedback, and suggestions I really appreciate it! I reached out to the builder so we’ll see how that goes. Assuming they don’t want to address it, from everything I’ve read on here I feel it’s safe for me to assume as long as the toilets are functional, there should not be an issue in me waiting a while to address them i.e 6-8 months? There’s a lot of other places I need to prioritize spending right now.
WJcandee
Wise One
Send him a photo of the water spot in the "worst one", and the shims and the level. The thing clearly wasn't installed properly. Tell him it's embarrassing to you for people to see something like that in your home. It should be embarrassing for him, too.
