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Community and Q&A

Wall Hung Ultra High Efficiency (0.8gpf or less) Toilets?

bcade | Posted in Green Products and Materials on

Hey Folks,

I’ve got a situation where I specifically need a wall hung or other very shallow toilet (due to a ~24″ depth limit for clearance) that meets the UHET level of 0.8gpf maximum.

I haven’t been able to find anything from the usual suppliers of wall hung toilets, and I got a response from Niagara that they have no intentions of offering a wall hung product.

I’m hoping someone here might be able to steer me in the right direction if either there is an existing solution I’m not coming across, or perhaps insight into the pipeline for other manufacturers.

For those curious why I’m in this situation, the project is in the Monterey Peninsula of California where we have a moratorium on intensification of water use. Basically I have a set number of fixture units from a SFH being demolished that are just enough to build two units, each with one bathroom and a washing machine IF all of the fixtures are the most efficient. Dropping from 0.8 to 1.28 gpf on both toilets would mean one unit will have to lose a washing machine, which I’d strongly prefer to avoid.


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  1. Expert Member
    BILL WICHERS | | #1

    I can't point you towards a wall hung unit that meets your needs, but I would recommend you try at all costs to avoid the use of a wall mounted toilet in general. Wall mount toilets inevitable get loose and have other problems that can be annoying to deal with down the road. I've had this issue many times in commerical properties which seem to much more commonly use wall mounted fixtures than residential projects do.


  2. Expert Member
    Akos | | #2

    If I remember correctly, for calculating the effective GPF of a dual flush, you take 2 low flush and 1 high flush. There are a number of 0.6/1.28 wall mounts which are effectively 0.8GPF.

  3. onslow | | #3

    Brian, Just started my own toilet quest for a spring build. I prefer Toto, which has choices I think fall into your requirement range. Be sure to scroll down from the first ones they show you. Like the post office, they show you the most costly option first. I did not know there are $17,000 toilets!

    If you want to branch out on brands, try looking at these two from Overstock. Never installed a wall hung, but I have read that you need a deep enough wall to put the mounting frame and tank assembly. Not sure I would enjoy having to service one. The one certainly is unusual looking and seems to be less than 21" from the wall to lip.

  4. bcade | | #4

    Thanks everyone for the great feedback!

    Bill, you're absolutely correct, up front costs, install labor, and long term costs will all be far beyond that of a normal toilet. Its one of a few upgrades I'm considering for an otherwise pragmatic build.

    Akos, the calculation is not something I considered, I'll definitely look into that more. That being said, per my math the 0.6/1.28 setup would come out just over the limit at 0.82.

    Roger, I should have clarified, the language they use is "0.8 gallon maximum"

    1. Expert Member
      Akos | | #5

      The spec calls for 0.8 (since there is no extra decimal), the 0.6/1.28 setup should work.

      As a general rule, try not to design yourself into such a small corner. I've done a number of micro 2 bed apartment designs (500 sqft) and managed to fit standard toilets (there was some 2x3 and 2x4 on flat portion walls though). Saves cost and makes life easier down the road.

      I do like the clean look of wall mounts. Never had issues with it coming loose at home, the back frames are pretty beefy on these things.

      1. bcade | | #6

        Great point on the decimal points, it certainly couldn't hurt to give it a shot.

        I do have a few ways to make a traditional toilet work in the space, that being said the wall hung would allow for far and away the most elegant solution.

  5. gusfhb | | #7

    I think finding the 3 inches is easier than finding the toilet you seek

    Outswing door, narrower door, recess in the wall

    Of course the regulation is silly, here in the people's republic, they regulate bedrooms and rooms as having 3 toilets in a 1 room apartment would not change water use

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