Learn how to make a toilet tank sink!


We all know that an average toilet uses excessive amounts of clean water per flush. And that makes up a large part of every household’s water consumption! Wouldn’t it be nice if we could maximise the use of this clean water before they are flushed down the bowl? A toilet tank sink makes that possible!

Toilet Tank Sink

But how exactly does this idea work? Well, you can use water that flowed from a faucet from a sink on top of it as fill water for the toilet. This way you can wash your hands with that clean water before it is used for flushing on the next toilet use. Simple as that!

Now this step-by-step tutorial will show you just how easy it is to make your own toilet tank sink. You’ll see that the materials used here are scrap or recycled to make the whole idea inexpensive. But if you are keen on aesthetic design, you can use other better-looking materials.

Have a look at some of the toilet tank sinks other DIY-ers have made and start reducing your water consumption by making one yourself!

Is this going to be your next home improvement project?

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  • 9×20″ Wood Sheet
  • Small Plastic Funnel
  • 1/2″ diameter Copper Tubing
  • 8″ diameter Metal Bowl
  • 4′ long, 1/8″ inside diameter Vinyl Tubing
  • 4 L-Brackets
  • Small Wood Screws
  • Scrap Paper
  • Silicone Latex Caulking Glue
  • Steel Binding Wire


  • Measuring Tape
  • Hand Drill (with 1/2″ Spade, 1/8″ Drill Bit and 3″ Hole Saw)
  • Jigsaw
  • Center Punch
  • Sharpie
  • X-acto Knife


Toilet Tank SinkLocate parts and trace: Remove the lid from the toilet tank. Locate the over flow tube, gently remove the rubber tube going into the top of it.

Toilet Tank SinkTake the small plastic funnel and stick it in the tube. Now take a straight edge and span it across the walls of the tank next to the funnel, and mark the edge on the funnel.

Toilet Tank Sink

Now remove the funnel and lay a piece of paper of the tank and trace out the walls and the location of the over flow pipe in relation to them.

Toilet Tank Sink

Next, take the lid from the tank and trace it onto the sheet wood.

Toilet Tank Sink

Cut out the lid: Cut out the shape of the lid with a jig saw from the wood and clean up as necessary with sand paper. Now take the paper tracing of the tank and cut on inside wall line with scissors. Now center the tracing on the new wood lid, and take the center punch and mark the center of over flow tube on the wood lid. Using this mark as center drill a 3 inch diameter hole with the hole saw.

Toilet Tank Sink

Making the sink: With a marker, extend the line on the funnel so that it goes all the way around, cut on the line with an X-acto knife.

Toilet Tank Sink

Now take the metal bowl and create drain holes in the center with a small drill bit, making sure the final drain is no bigger than the top of the freshly cut funnel.

Toilet Tank Sink

Next place the funnel on the bottom of the metal bowl and apply liberal amounts of caulking glue on the crack between the bowl and funnel.

Toilet Tank Sink

The faucet: Made from copper tubing bent into an upside down “J”. To bend the tubing without kinking it, tightly wrap the wire around the section to be bent and carefully bend it with your hands, re-tightening the wire occasionally. Trim off the extra tubing with a tubing cutter.

Toilet Tank Sink

Drill a half inch hole with a spade bit, 3 inches away from the large hole in the wood lid. Force the long end of the copper “J” into the hole, friction should hold it in place.

Toilet Tank SinkBracket in place: To keep the wood lid from sliding around on the tank, you can attach brackets. To figure out where the brackets need to be, flip over the lid and center the paper tracing of the tank on it.

Toilet Tank Sink

The brackets should be against the outer edge and attach with small wood screws.

Toilet Tank Sink

Installation: Back inside the toilet tank, locate the rubber tube that was inside the over flow tube and follow it back to the float valve, and pull it off.

Toilet Tank Sink

Now attach the 4 foot vinyl tubing.

Toilet Tank Sink

Push the other end of the vinyl tube through the bottom of the wood lid’s half inch hole and up though the copper tube until just before it sticks out the other end of the copper tube.

Toilet Tank Sink

Now lower the new lid onto the tank making sure the vinyl tubing does not interfere with the internal mechanisms in the tank. Take the metal bowl with the funnel attached and make sure the glue is dry.

Toilet Tank Sink

Now look down the 3 inch hole in the lid and you should see the over flow tube.

Take the bowl and funnel and lower it onto the hole, the funnel needs to go into the over flow tube.

Toilet Tank Sink Finished

Finished: The sink is now complete. I would recommend putting some kind of water proofing on the lid to protect the wood.
Check out the video of the sink in action:

Thanks to Gregory Lavoie for this great project!