# Ideal toilet flange height in relation to finished floor



## jaketrades (Mar 2, 2017)

I had to pull my parents toilet this weekend and noticed the flange was a 1/4" above the finished floor. There was also a bunch of built up mortar under the toilet. It got broken away as I was pulling the toilet.


I bought one of these new wax-less toilet gaskets and reinstalled the toilet as per the instructions for toilets wiht flanges 1/4" above the finished floor.. The toilet was wobbling all over the place. I had to shim the hell out of it, but got it seated. 

So my question is, should a toilet flange be flush with the finished floor? I've read varying opinions. Some people say flush and others 1/4" above the floor.

I'm about to wrap up work on my own bathroom renovation, and I believe I roughed it to be 1/4" above the finished floor. I can get it flush by using 1/2" cement board on the floor. I dont want to to mess around with shims.


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## chandler48 (Jun 5, 2017)

1/4" AFF presents no problem with a wax ring. I have never used one of the newer waxless rings so I don't know the solid profile and they could cause a problem. I would not shim the toilet. I would use a wax ring so it will sit solidly on the floor. If you see the need for shims afterwards, then it is the floor that is causing the problems, thus the mortar that someone installed on the first one.


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## jaketrades (Mar 2, 2017)

chandler48; said:


> 1/4" AFF presents no problem with a wax ring. I have never used one of the newer waxless rings so I don't know the solid profile and they could cause a problem. I would not shim the toilet. I would use a wax ring so it will sit solidly on the floor. If you see the need for shims afterwards, then it is the floor that is causing the problems, thus the mortar that someone installed on the first one.


There was a wax ring there previously and original installer felt the need to install a mortar bed toward the tank side of the toilet. You're probably right on the tile floor being out of level in the toilet area. 

I was talking to a plumber yesterday and he said the flange had to be flush with the finished floor as required by code.

These new waxless gaskets are great by the way. Water tight, no wax mess, and you can pull the toilet and reuse it again and again.

I've used both of these in the past. No mess, no fuss.

https://smile.amazon.com/dp/B00R7D3...eature-pcomp-wm-3-wm-8-wm-1&ref=aa_pcomp_prc1


https://www.amazon.com/Sani-BL01-Waxless-Toilet-Gasket/dp/B005K89RQU


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## rjniles (Feb 5, 2007)

"
I was talking to a plumber yesterday and he said the flange had to be flush with the finished floor as required by code."

Flush with the finished floor is hard to interpret. Does this mean the top of the flange or bottom of the flange is level with top of floor. Many people will misinterpret.

Best stated as flange sits on top of finished floor.

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## SeniorSitizen (Sep 10, 2012)

Top of flange near finished floor level or buy yourself a bag of shims because the odds of you needing them is about 10-1. The reason for those poor odds is there is no standard for the recessed depth in the toilet base, but a wax ring is available in 1" thickness everywhere they're sold. The wax ring on the pulled toilet is an example of the flange above the finished floor. The pictured wax ring doesn't need to look like that to seal. I can guarantee that toiled rocked without shims.


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## jaketrades (Mar 2, 2017)

rjniles; said:


> "
> I was talking to a plumber yesterday and he said the flange had to be flush with the finished floor as required by code."
> 
> Flush with the finished floor is hard to interpret. Does this mean the top of the flange or bottom of the flange is level with top of floor. Many people will misinterpret.
> ...



I meant the top of the flange is flush with the finished floor.





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## TheEplumber (Jul 20, 2010)

Per UPC, the flange 'shall rest on an approved base'
The interpretation manual clarifies this as '1/4" above the surface the toilet will be resting on'
IMO, If a toilet will not set on a flange installed this way, then your toilet is not built to code standards.


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## SeniorSitizen (Sep 10, 2012)

Possibly I overlooked something but I didn't find anything in the codes about toilets not meeting a code for flange height.


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## TheEplumber (Jul 20, 2010)

SeniorSitizen said:


> Possibly I overlooked something but I didn't find anything in the codes about toilets not meeting a code for flange height.


I quoted IAPMO's answer from their Interpretation Manual.
It is not published on the web. So google won't help you there

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## SeniorSitizen (Sep 10, 2012)

I'm trying to determine if the toilet manufacturers itself have a code to follow. If not the height of a flange is moot.


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## SPS-1 (Oct 21, 2008)

Its amazing that I can find a toilet flange discussion so interesting. I was able to find CSA/ASME spec for toilets HERE . It does not specify the flange, but it does specify the toilet design -- which is to have a .5 to .75" recess. Probably would work with flange either flush or above, but probably I would say geometry looks better with flange above.


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## jaketrades (Mar 2, 2017)

So this toilet flange issue made me take a close look at the flange height of my remodel project. Im gutting a place (2 bathrooms) and I measured both toilet flange TOPS off the subfloor. Bathroom One is 3/4". Bathroom 2 is 1 3/8". Don't know how that happened but I see I'm in a pickle on the latter.

bathroom 1 : 1/4 cement board + 5/16 tile + 3/16 thinset = 3/4". Flange is flush with the finished floor.

Bathroom 2: 1/4 cement board + 5/16 tile + 3/16 thinset = 3/4". Flange 5/8" above the finished floor. Not sure how I bleeped up that bad.


I thought about a couple of solutions:

1. Use 1/2" cement board on the floor. That still leaves the top of the flange 3/8" above the finished floor.
2. Find a shorter toilet flange if they exist
3. cut 1/2" off the closet elbow. Duct tape the cut line. Start the cut in all accessible areas with a 4 1/2" angle grinder and finish the cut with a sawzall with cast iron blade.

Any advice?

Thanks.


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## Calson (Jan 23, 2019)

It is not "code" but preventing water from damaging the subfloor that should be the concern. A flange needs to be screwed into the subflooring and its height depends on whether it is cast iron, steel, or plastic. 

The cheapest but least effective seals are the wax doughnuts. Better are the green ones that provide a seal even if the toilet connection is on the high side. The toilet base should sit solidly against the floor as a rocking one is going to leak. You can shim the toilet and that is often done but it is not something I would ever do. 

The problem is that someone put down motar and the flange is too high and fixing this would entail cutting off the flange and putting in a new one - something that is easier said than done in many situations (hence the practice of shimming).


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## ZZZZZ (Oct 1, 2014)

I just reinstalled a toilet after tiling the floor. I used one of these, takes care of flanges too high, too low and uneven. 

Perfect Seal Toilet Wax Ring with Bolts










https://www.homedepot.com/p/NEXT-by-Danco-Perfect-Seal-Toilet-Wax-Ring-with-Bolts-10826X/206393853
.
.


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## jaketrades (Mar 2, 2017)

ZZZZZ; said:


> I just reinstalled a toilet after tiling the floor. I used one of these, takes care of flanges too high, too low and uneven.
> 
> Perfect Seal Toilet Wax Ring with Bolts
> 
> ...



It can handle a flange up to 1/2” above the floor. I believe they mean top of the flange.


“It accommodates flange heights from 1/2 in. above the floor to 1-1/2 in. below the floor”


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## jeffnc (Apr 1, 2011)

jaketrades said:


> I was talking to a plumber yesterday and he said the flange had to be flush with the finished floor as required by code.


That's incorrect. The bottom of the flange rests on the finished floor and is therefore flush with the finished floor.


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## jeffnc (Apr 1, 2011)

SPS-1 said:


> it does specify the toilet design -- which is to have a .5 to .75" recess. Probably would work with flange either flush or above, but probably I would say geometry looks better with flange above.


Right on both counts. Floor-flush flanges are the ones that need the Jumbo wax rings.


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## nebojsa (Nov 10, 2020)

The bottom of the flange rests on the finished floor .


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## Charliehustle78 (Dec 22, 2020)

jeffnc said:


> That's incorrect. The bottom of the flange rests on the finished floor and is therefore flush with the finished floor.


Flush would mean top of flange not bottom. When something is called flush it means it's on the same plane as whatever it is being flushed up to.


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## jeffnc (Apr 1, 2011)

Charliehustle78 said:


> Flush would mean top of flange not bottom. When something is called flush it means it's on the same plane as whatever it is being flushed up to.


There are 2 planes on a flange - the top and the bottom. For a toilet flange to be installed correctly, the bottom of the flange is flush with the finished floor. You can get it to work other ways, but that is standard.


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