View Full Version : Tankless versus Tank toilets - which to consider for church?
03-02-2010, 07:42 PM
My local church is looking to put in two new bathrooms in the basement so that restroom facilities are more accessible to the food pantry clients. I'm part of a committee that is trying to come up with specifications for this project.
One point of discussion is tankless versus tank toilets. In our existing upstairs bathrooms, we are currently using tank toilets.
It's my understanding that you need 1" supply lines for tankless. I believe we have at least 1" water main if not larger due to the size of the church (15K sf?) and the use of sprinklers. I read that the advantages of the tankless is that they take a bit less space, use less water, have better flushing and are more reliable to operate.
Is this correct?
Are there any cost differences (e.g, tank is cheaper than tankless?)?
We do have a septic system so it would be advantageous to use less water if possible. I'm planning to chat with our plumber but if you have any advice, it would be appreciated. Thanks!
03-02-2010, 11:25 PM
To run several 1" valves, you would need something like a 1.5" or 2.0" from the street.
For two bathrooms added to the end, you would need 1.5" pipe up to that point assuming you had a 1" meter at the street.
If the meter is a 3/4", then it wouldn't work. The city will know what size meter you have.
Two Flushometer valves would require sizing for 70 fixture units.
Normally, a commercial tank toilet would be sized for 5 fixture units each for a total of ten.
As you can see, that's a huge difference.
There is no water storage, so when the valve is flipped, the pipe volume needs to be able to keep up.
Consider that each time a tank toilet refills and it takes up to a minute on the refill, you start getting the idea.
At my church, we used a 2.0" line from the street, for two urinals with 3/4" valves, and all of the toilets used tanks.
I wanted a system at church that was quiet beyond the walls.
I had been in churches before when the amount of noise had been distracting.
Also, severely undersized. It wasn't good.
Since all bowls now use 1.6 gallons or less, there is no performance "edge" by making the bowl tankless.
In fact, many tankless bowls do not work as well.
The thing I hate about tankless bowls, is the overspray you can get too.
Nothing like getting your legs sprayed when you are done.
A flushometer or a tank will use 1.6 gallons or less.
There really isn't any water savings either way.
If you go tankless, it will require perhaps more of an investment in the interior piping then what you have. Pipe sizes may need to be upgraded.
This isn't to say that aren't good reasons to using a Flushometer sometimes in a commercial building.
But when they are being used, it's designed from the meter in. Everything is sized for it from the time the drawings have been drawn and engineered.
There, that should preserve my invitation to the Sloan factory this month.
09-02-2011, 03:59 AM
What is a tankless bowl?
09-02-2011, 04:16 AM
It is a toilet with a flushometer,one that a valve,you know one of those shiny silver things that you see in commerical buildings.
quote; advantages of the tankless is that they take a bit less space, use less water, have better flushing
they take the same space, use the same or more water depending on the bowl, but USUALLY do flush better. They are also noisier, but if there is going to be a lot of traffic, they "recycle" faster. They can cost more depending on the quality of the tank type you would use. Available water supply is the real determinant as to whether you can EVEN consider a tankless model.
09-02-2011, 09:44 AM
In the church I go to, we went with tanks. It's much quieter. I asked them, Do you want to constantly listen to toilets flushing while in the lobby?
Now, it's quiet as a church.
And again, for toilet bowls without tanks, you need a larger meter, larger main supply line, and a larger line right up to the last bowl. We're talking maybe up to a 2" line from the street with a 1.5" meter.