This Instructable is a step by step description of the process of adding a sink to the top of a toilet allowing the use of the clean water before it goes into the bowl.

Water is a precious resource and our everyday lives are immersed in consuming it. The average toilet uses excessive amounts of water. This hack allows you to minimize some of that water consumption.
I wanted this instructable to be simple enough that anyone could build it with basic tools and materials. I also tried to be material conscious with this project in that: many of the materials are recycled from other things (sheet wood and copper tubing) or second hand (metal bowl), and that it is put together using screws and friction fittings so when the sink has finished serving its purpose it can easily be taken apart and the parts can be recycled.

Step 1: Materials


9inchx20inch piece of sheet wood
Small plastic funnel
Copper tubing half inch outside diameter
Metal bowl approximately 8 inch diameter
4 feet of Vinyl tubing 1/8 inch inside diameter
4 "L" brackets and small wood screws
Scrap paper
Silicone latex caulking glue
Steel binding wire

Hand drill
Jig saw
1/2inch spade drill bit
1/8inch drill bit
Center punch
Hole saw 3 inch
Exacto knife
Unfortunately the sink waste water will only displace water already in the bowl forcing it down the drain. The slow trickle will not flush the bowl clean. By the laws of physics no water is saved.
<p>Pretty good. I'll make one of those. Thanks.</p>
<p>I'm wondering about hand soap going into a septic system?</p>
<p>if you have a septic system then all your water goes through the same pipes to the septic tank soap and all</p>
Why has no one pointed out that, unless someone else is paying your water bill, there is nothing free about it?
<p>using the same water twice.</p>
Because, it is TECNICALLY free. <br><br>This uses the water that goes in the bowl. So it still goes in the bowl, you just wash your hands on the way by.
He is using the same water twice and paying for it once.
Agreed TravisL7. Why would you &quot;steal&quot; water from your toilet to wash your hands, when the toilet water costs the same amount as the stuff coming from the sink faucet.<br>
The water being used, is normally wasted. It just goes into the bowl. By having it go through this system, you can wash your hands with it on the way by.
<p>The water is still wasted, because the flush has already cleaned the bowl; the handwash waster water just goes down the overflow and through the bowl into the drain - the level in the bowl doesn't change by &quot;magic&quot; to accommodate the extra water.</p>
<p>you're using the same water twice.</p><p>once to wash your hands and the second time to flush the toilet</p>
He is using the same water twice and paying for it once.
<p>I do hate to sound negative, but this 'hack' isn't that clever IMO.</p><p>Washing your hands in such an uncomfortable position is bad design: worse,</p><p>washing your hands on a toilet is poor hygiene design ( Treehugger has written a lot about the problems inherent in placing washing facilities in close proximity to a lavatory pan ). And having 'grey' water sitting stagnating is another area of concern.</p><p>I do share the author's desire to avoid waste and am planning some kind of system in my house. I'm in the UK where water shortages are considerably less severe than in the USA, but I still abhor waste, especially since the cost of cleaning water is considerable.</p><p>I'm also lucky in having a large roof area. When it rains the entire run-off is channelled into a big bucket and, as yet, I cant cope, but it isn't finished. The master plan is to collect it in one of those 1000L containers ( in the form of a cube: do you have them? ) This will be pumped into the cistern, with suitable controls. The water should be clean enough not to cause problems on standing.</p><p>As for 'grey' water: there will be another collection system whose contents are intended for the garden, so, if it gets a bit yucky, it wont matter too much.</p><p>Keep up the good work.</p>
<p>beware of bird droppings, rotting leaves and such.</p>
<p>Right! I think this is a terrible idea. </p><p>Not wasting water would be solved better with reducing the water level you store in the tank and following these simple principles.</p><p>If it's yellow let it mellow.</p><p>If it's brown flush it down.</p><p>Plus, I don't know what a vegan hippy diet does for stool but what doesn't evaporate into rainbows and lollipops should flush with less water.</p><p>:-)</p>
<p>This type of toilet sink is standard in Japan, and they have no problems with it.</p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/dB31Es7Z-iU" width="500"></iframe></p><p>Makes the toilet easier to clean too. No downside. *^_^*</p>
<p>The greywater stagnation is only an issue in a restroom that gets very little use. Our house has 2 washrooms &amp; 6 people living here, to say nothing of visitors. The longest our toilets go without a flush is maybe an hour, 3 hours at night.</p><br>Besides, if you are using a handsoap with essential oils of tea tree, lavender, orange oil--the tank is going to stay fairly clean, regularly. <br><br>If you leave on a trip, just pour a dollop of bleach into the tank before you go, and if necessary, a dab when you get back. It requires very few ppm (parts per million) to make an unsuitable environment for bacteria. Colloidal silver also works.And there are MANY food-grade enzymes available, as well. Plenty of options.<br><br>Besides, the toilet bowl is going to be cleaned as usual anyway; just seems like such a non-issue.<br><br>As for awkward placement--also depends on your bathroom layout. Our guest bathroom would be fine--plenty of space beside the toilet to stand comfortably; not an option in the master bath, though. So I am trying this in the guest bath. Finding a different set up for the other one.<br><br>But I'm tired of flushing perfectly good water down the toilet.<br>Literally.<br><br>Cheers!
<p>Excellent point, null. A fundamental principle of greywater is you never store it. What this instructable will do is result in a slimy, foul-smelling toilet tank.</p><p>But the basic idea has merit. Ken Kern wrote a book in the 70's called &quot;The Owner-Built Home&quot; in which he described a toilet design that used greywater for flushing. It did not store the greywater, but instead ran it through a sluice that flushed away the solid waste. That would work.</p>
<p>@ iamuke: thanks. I suggested rain water as a better alternative. Well, it is, but that, too, may have problems of its own ( gosh, this environmentalist stuff is tricky ) One way round this is to have a number of smaller containment vessels for the rain-water run-off. I don't reckon that would be so hard. Fill the cistern with the oldest batch first. Possibly have a system where the newer water gets pumped into the older containers as they empty. If the older water starts getting manky, ditch it on the garden. Brilliant, if I say so myself. That will be 25 guineas. Have I missed anything?<br>Bruce</p>
<p>Coy fish.</p>
So you're the person who has my handle. Nice to run into a fellow Sianeee!
<p>Your &quot;clean&quot; rain water will soon start to stagnate as it has collected dust &amp; pollutants just from falling thru the air, plus what it has washed from your roof in the form of dust, leaves, bird droppings, etc. :((</p>
<p>@null, I agree with your concerns. I've never seen a cistern with a hose like that into the overflow, I think UK Regulations don't allow such things?</p><p>Regarding grey water: It's not a good idea to store grey water for long periods, the water gets stale and loses oxygen. Please have a look here for more details: </p><p>http://greywateraction.org/greywater-faq/</p>
<p>Hello Agulesin,</p><p>You dont say where you are from. I dont know if UK regs disallow this hack, but, as I say, I think the design is flawed and wouldnt use it myself. Having said that, at least the guy is trying. His design is not rubbish, but I think it could be improved.</p><p>My own plan wont get installed for some time because other things take priority. Nevertheless, the idea is there: divert the roof run-off into a HUGE container. It can be used ad libitum to fill a cistern. The power required to pump the water is not great, so you could use a solar panel + battery to insulate yourself from problems with the Grid. Remember, this is just one idea and maybe it could be tweaked. Suggestions always welcome, if accompanied by a 10UKP note.</p><p>Regards</p><p>Bruce</p>
<p>The water has already passed through your meter, or is otherwise paid for, so how can it be free?</p><p>I'm happy with the desire not to waste water that you have paid for, but if you have sufficient overflow to be able to fill the sink then your cistern needs a repair as the supply is meant to cut off when it is full.</p>
<p>you could save water by peeing in the tank and using that to flush the solid waste!</p>
<p>Have you ever tried to do that? please let us know how it's done!</p>
i'm sure the folks at instructables.com could come up with a good way. but you gotta admit, we do waste almost a gallon of liquid a day.
<p>And then use it once more to wash your hands..? Free heated water!</p>
I'm going to try this in my guest bathroom hopefully later this month. I'm also going to run the intake through an &quot;at the sink&quot; mini water heater that will raise the temp up to about 100F. Slightly warmer than body temp, more energy efficient than our hot water tank.<br><br>I'm also considering installing a carbon filter in the drain. Will play around with it.
<p>I saw this in several countries we stayed on our round the world trip in 2010-2011! So many countries have limited fresh potable water sources, and the toilet water wasn't necessarily the potable kind, but good enough to wash hands </p><p>It would have been great if you'd also finished the wood board so it was a bit more decorative.</p>
Great concept! Point is, saving water, is water saved. No matter the quantity. I believe a lot of people missed the fact that the funnel went in the over flow, so the grey water went into the bowl and didn't sit in the tank. Liquid hand soap would be best versus bar soap. Great job :)
<p>Thanks for sharing this with us. I made an instructable for my own version of the toilet sink using 3D printed parts. Check it out here: <a href="http://www.instructables.com/id/Save-a-Little-Water-with-a-3D-Printed-Toilet-Sink/" rel="nofollow">http://www.instructables.com/id/Save-a-Little-Wate...</a></p>
<p>I lived in Japan as a &quot;bimbo&quot; student and I had to pay a exhorbitant water bill and disposing of water bill every month ($_$) so I was forced to use this device even I had a sink. Also during winter if you had to do your business during late freezing night it was a blessing. I miss it so I will try no matter what they say.</p>
<p>I am in the process of making a very small guest house in my backyard and will use a version of this. I think I will make the &quot;sink&quot; just next to the toilet and then have a tube going into the tank. It will make if more comfortable for people to not have to straddle the toilet to wash. In your case, I would suggest getting something instead of the particle board as it will quickly breakdown from the moist environment under the lid. I found a really nice white cutting board I plan to use. </p><p>For those worried about the water being soiled...it us coming straight out of the water system, through the sink and then into the toilet. There is no contamination.</p>
<p>Nice job! Here's mine: the faucet is plumbed into the water line so I can use water as needed rather than just when flushing. I chose a rather large funnel for the bowl so I could pre-soak laundry as needed. </p>
<p>I'm impressed. How long did that take?</p>
<p>As I recall it took a few hours. The lip of the funnel is captured between the two layers of 1/2&quot; (or metric equivalent) Baltic Birch plywood. I used a trim router on a small arm to rout the holes and the shoulder which accepted the funnel's lip. That was the tricky part. The rest was pretty straight forward.</p>
<p>Very nice job.</p>
<p>The real first step- Swap out that old water-guzzling 3.5 gpf toilet for a 1.28gpf or less toilet. You'll save nearly 13000 gallons of water. At the very least, retrofit it to use less water.</p><p>I'm from California, where we've been stricken by the drought. We've let our lawn die out and have retrofitted all our water fixtures.</p>
<p>It may save water, but not much. The heck I found one factory made like that about 1 year ago and it would take 60 years to pay for itself in my household.</p><p>You may save a few quarts of water, but health risks are 100 times higher because of it.</p><p>Just 1 doctors visit will ruin your water savings for the next 50 years.</p>
<p>I have photos of a commercial toilet I took two years ago in New Zealand but was unable it upload the photos. I photographed the toilet at the time because I was so amazed at such a intelligent idea! </p><p>Thanks for the creative hack! Brilliant work and instructables!</p>
<p>Wrap your wood board in vinyl wrap! It would make it looks soon much better. Sand the edges and wrap everything. I found white matte vinyl wrap on a website like tourvinyl.com You could use imitation granite or wood but you'd have to Google to find it.</p>
Since Hackaday revived this 'ible, I thought it a good time to revisit, reread, and comment.<br><br>If renovating a bathroom, or designing a new one, my main complaint about this idea could be easily solved. That is, you have to straddle the bowl to use it! In building new/remodeling you could have the toilet rotated 90 degrees, on a kneewall and be able to stand on the side of, or behind the tank. Much closer to the sink portion.<br><br>There aee a few comments about wasred water and...well, top mount dual flush valves would mitigate that, AND make JUST washing your hands 'waste' less water without having to rig a seperate faucet valve.<br>Having grey water sitting in the tank may not be the best for the plumbing parts, so occasionally dosing with bleach or other scum remover will be required, and keep an eye on the plastic and rubber parts for leaks; especially the rubber flapper.
<p>Add a foot valve for only flowing water exactly when you are washing</p>
<p>Cool way to use the same water twice! They should offer store bought toilets like this - (or do they already?)</p>
<p>I think they have them in Japan. </p>
<p>I think it is a very good idea and showed great intuition. I do understand all the negative comments so how about them people come up with their own project and make it, then they can show how good they are. Thanks Gregory </p>

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