View Full Version : Recirculating Shower

07-18-2010, 12:49 AM
Anybody attempting a recirculating shower system for water conservation and perhaps water pressure for massage shower heads?

I am thinking a DIY: pump and reheat, similar to: http://www.builditsolar.com/Experimental/RecircShower/KenShower.htm

Not expensive as in the Quench system

Would likely just use 2 shower heads and a hand held, for both continuous and recirculating.

Would love to hear of anyones experience attempting this kind of thing.

07-18-2010, 07:30 AM
I am sure you are trying to be green and live off the grid, and all that crap. Silly me, I still believe the plumbing codes are there to protect the health of the nation, and what you propose would make an inspector faint!!!!

Once the water enters the tub drain, it is GRAY water. If you think it is sanitary, tell me what is rinsing out of your armpits or buttcrack! Codes like the UPC are now friendly to gray water reuse, but for sure, the one thing gray water can never do is touch a human .

If you are serious about this, we will not talk you out of it, but if you are in any kind of larger city where there are inspectors, etc, or if you ever plan to sell that house, I would reconsider that plan. There are other energy saving devices, like heat recovery systems on the tub drain pipe, that you could look into.

07-18-2010, 12:13 PM
Was I too harsh? Anyone else have an opinion?

07-18-2010, 01:08 PM
In the UPC code, once it becomes gray water, it can't come in contact with potable water systems.

Grey water pipes are on a "separate" system, and must be marked the entire way that they are "gray water" pipes.

Grey water systems have never been approved for bathing.
They have been allowed for toilets an urinals.
There is no such thing as a Recirculating Shower in the code book.

The intent of this design seems to be similar to that of a jetted tub, reusing the bathing water by recirculating into the secondary shower heads.

07-18-2010, 02:09 PM
No Jimbo I think you said it about right...

07-18-2010, 06:33 PM
Maybe, just maybe (but I doubt it) this would be okay IF the pump was connected to different showerheads so that there was no way to cross-connect the potable and recirculating systems.

But no way would it be considered "green" because the amount of power used for the pump and the heater would far outweigh the savings in water.

07-21-2010, 03:29 PM
Ha ha -don't even remember attaching that image; sheeesh.

Long showers are my addiction I guess.

The idea of recirculating the water has been around a while, but Quench is the only manufacturer I found.
I suspect their installation would pass code.

One simply soaps down and rinses before turning on the recirc.
The water would then be no dirtier than a jacuzzi as Terry points out.

Ya, recirculating water after the drain seems suspect, but it's certainly before the trap.
Quench seems to use a basin and pop-up drain to divert the water to a secondary drain.
Their price tag is too much for such jollies though, so investigating if DIY is over my head.

Liked the simplicity of the "KenShower" tapping into the drain before the trap.
Keeps everything behind the scenes and no extra penetrations to waterproofing/tile.

Looking to drain past a pit under a shower seat before trap.
That, for now, would give me the option to experiment later.

Likely will use the same 2 shower heads and hand held.
Want to be able to pull out if it goes sour.

I do note the possible misadventure of taking water at your feet and dumping back on your head above your mouth without treatment.
Something to think about. This might occur, but less likely, in a jacuzzi, and one would want to be mindful of it during use.

I note the concern of using the same shower heads should any bacteria get in the lines.
Quench uses a sanitize/rinse cycle for 1 minute after use. Not so easy to duplicate perhaps.

07-22-2010, 01:34 PM
I hear you about the long showers, for me a short shower is fifteen minutes. Still, I don't like your idea from the standpoint of possible contamination of the supply system.

I don't know what your cost of water and sewerage is but for me the cost of water is minimal, less than $15 a month and my sewerage fee is a fixed amount of just under $50 a month regardless of the amount of water run. That leaves the cost of heating the water which for me is about $10 a month so there is no incentive to lessening the amount of water I use while in the shower.

However, if I were to do what you desire I would have a small sump, around five-ten gallons or so with a submersible pump. The drain would go to the sump and the sump would have both an overflow and a manual drain to the sewer trap. I would never consider connecting the pump to the same shower head(s) as the potable water and I would be certain to open the manual drain from the sump every single time when I finished showering.

07-22-2010, 04:03 PM
What happens when you have a main line stoppage in the home? In many systems the low point is the tub. That would put raw sewerage in the tub & also in your pump. I don't think I would like to be the first to take a recirculating shower after that.


01-21-2011, 09:14 AM
I am in the planning stage of a new home. I am very interested in this issue because I like to take long hot showers.

I am trying to understand the differences between a recirculating shower and a jetted tub. I am not a plumbing expert, and I certainly do not fully understand all of the issues in the plumbing code. I am offering this to induce replies from those that know this material better.

These are the issues I have identified that create potential problems for someone wanting to build a recirculating shower system. Please add to this list if I missed some issues:

1) The shower head should not be shared between the fresh water and the recycled water. I understand enough about fluid dynamics to see that the potential exists for the pump to push water back through the plumbing to the point of feeding other fixtures in the house. This is a very bad idea.

2) One of the writers in this thread defined grey water as water that has passed the drain. Is that correct, or is the definition water that has passed the trap? This distinction is clear in "Kenneth's" recirculating shower. He is drawing water after the drain but before the trap. My jetted tub draws water from a source independent of the drain. It has its own opening about 3" above the bottom of the tub. Is this independent opening necessary to avoid any issues with grey water? If this is the case, it seems that the issue is more definitional that practical. I don't really see the difference between what "Kenneth's" system does and what my jetted tub does.

3) Do jetted tubs do anything to sanitize the water passing through the jets? I have seen a number of jetted tub systems, and I have never seen anything more than a simple hair filter. If not, it seems that the issue of "pits and cracks" is no different for recirculating showers than for jetted tubs.

4) If I were to move the jets on my jetted tub so that they were 6 feet off the floor, and replaced the jet nozzles with shower heads, have I done anything that violates code?

5) My jetted tub does not have a heater. If I build a recirculating shower I would want to have a heater as part of the system. Does a heater have any impact on any of the other issues discussed here?

Thank you in advance for you thoughts!

01-21-2011, 10:20 AM
A jetted tub never tries to put the water back through the potable supply lines (i.e., the tub spout or shower heads). Recirculating it through those is the big and important difference. If you want to save energy, install a waste-water heat recovery system. Essentially, the cold water supply gets wrapped around a special drain pipe, preheating it so you don't need as much hot. It can recover a significant amount of the heat from a shower. Much more friendly AND totally legal and without potential cross-contamination issues. No way I'd want to deal with the hair and soaps and dead skin, etc. that would get recirculated...gross, that's why it goes down the drain to be processed and cleaned up.

01-21-2011, 01:52 PM
Although the code allows bathtubs, I do NOT consider them sanitary at all. Since people have been taking baths for a few thousand years, and mostly not dying from it, who am I to criticize??

01-21-2011, 05:42 PM
Filling a tub with water, regardless of whether you "circulate it" or not, is NOT the same as taking that same water and spraying it on your head, face, and body. The idea is lucirous and would fail any good code requirement and inspection. Technically, you cannot even use the water to your lawn irrigation system for potable water uses once it passes through the "backflow preventer" valve, and that water has not even left the pipes at that point.

01-22-2011, 10:23 AM
You forgot the shower head in the bottom of the tub pointing up.

And we wonder why the rest of the world makes jokes [and worse] about Americans wasting energy. One of your showers would keep a village in India in water for a week.

And since they bathe in fetid cesspools with dead cows floating by and survive, recirculating your bath water doesnt seem too bad.

The "FINAL" water after your hour shower would meet "code" in about 80% of the worlds population as drinking water.

Build a recirc shower, please, rather than waste all that heat and water.

01-23-2011, 10:57 AM
Thank you for the replies. It seems that this should be broken into two issues,
1) the "yuk" issue of using recirculated water, and
2) the technical issues of where, how, code issues, and anything else needed to make the system work properly.

First the "yuk" issue.

The response from the moderator included "Although the code allows bathtubs, I do NOT consider them sanitary at all." I completely understand this. If you are a person that believes that bathtubs are not sanitary, and shouldn't be allowed, then it is perfectly logical that you that would believe that recirculating showers are not sanitary and should not be allowed.

Another response included "Filling a tub with water, regardless of whether you "circulate it" or not, is NOT the same as taking that same water and spraying it on your head, face, and body." My definition of taking a bath includes washing my head, face, and body with the water in which I am sitting. Under that definition I disagree with the statement. Recirculating the water is the same as taking a bath. It contains the same contaminants, and is contacting the same parts of the body. In the case of a recirculating shower I can conventionally shower first, then turn on the recirculating feature after 90% of the contaminants have gone down the drain.

I suspect that the "yuk" issues is not going to be settled here. For my part I am not grossed out by bathtubs no matter if they recirculate or not. I therefore see no reason to be grossed out by a recirculating shower.

Now I would like to turn my attention to the technical issues.

Another response included "A jetted tub never tries to put the water back through the potable supply lines (i.e., the tub spout or shower heads)." I agree completely. I understand why a recirculating system should never use any of the same pipes or fittings as the potable water. I am not a code expert but I believe that doing so would violate both the letter and the intent of the codes. Therefore I think we can agree that any recirculating system must be completely independent of the potable supply lines. This is a very simple goal to achieve.

In a related question, does the recirculating system have to be independent of the drain? My current recirculating bathtub has a source that is independent of the drain. Is this a code requirement? This goes back to "Kenneth's" system. Since he draws his water past the drain but before the trap is his shower in violation of code? I have a copy of IRC-2000, but could not find anything in that code that deals with this issue. Can somebody point me at something that does?

I am also interested in the heat recovery system suggested for the drain water. The house I am planning is a single level on slab. Does this preclude the use of this type of system?

01-23-2011, 03:02 PM
How about that jetted tub with a heater incorporated, some do, and tee off of the lines or kill a few jets and run them up the wall to a spray head?

Now you shower while standing in a foot of water, and can be sprayed or soaked all in one shot.

Cheap and elegant solution, with all the seperation from incoming water incorporated.

As to heat recovery, I always think of a 1,000 roll of pex tossed in the septic tank to feed the water heater. But I suspect some "small" issues of contamination may prop up.

Take a look at jacketed wine tanks. Small ones are made that are meant for glycol to cool the innards. They would work safely in reverse, with the shower and tub the heat source. Insulate heavily.

I built a long water heater 4" pvc exhaust with a 2" inlet combustion air centered inside it for a Polaris. Cold exhaust!
Polaris used to ship the units with a short version of this included. For some odd reason, the added restriction stopped all combustion code failures.

01-29-2011, 06:44 AM
Is there some type of valve that can be connected to the two inch drain line that can be operated electrically, or can have an extended stem (extended by about three or four feet) that can block the drain to allow recirculation?

02-25-2012, 11:10 AM
Does anyone remember the small saunas that used to be popular? Why not build a shower size box like the old saunas, completely independent of the home plumbing. There could be a tank in the bottom, with a filtration system, heater and pump that recirculates the water that runs into it. Water can be filtered to be as clean as you want it, even purer than what comes out of the faucet. The problems mentioned above wouldn't be an issue, if my thinking is correct. I'm building a truck camper, and am contemplating installing such a setup. Seems rather simple.