If you are cloth-diapering your wee one, you’re quite used to being called a loon. If you are planning to build your own diaper sprayer, you can add at least one more person to the folks who think you insane, the plumbing associate(s) at your local home improvement store.
This DIY will show you how to build a higher quality (and safer) diaper sprayer than the commercially available units for the same price or even a bit less.
A diaper sprayer is basically a sink sprayer connected to the toilet which allows you to spray the poopy mess into the toilet while keeping your hands cleaner than the old dunk and swish technique. Many of the commercial units are just a sprayer tapped into the toilet supply.
My improved design has a shut off valve to take the pressure off of the sprayer when it is not in use and a check valve to prevent fecal contamination of your household water supply. This assembly uses a length of tube so that it can be mounted away from the existing toilet supply valve. The remote installation ensures that when you turn the valve several times each day, you are not transmitting forces to a valve designed to be used a few times per decade. The entire thing is mounted to the wall using bell hangers.

Step 1: Gathering Parts and Tools

Take a trip to your home improvement store or plumbing supply house. Or your father-in-law's basement.
You basically need a T fitting to connect into the toilet supply, a check valve, an isolation valve, a kitchen sprayer, and nipples and fittings to connect all this together.
I ended up with this
three ½” close nipples
two 1” bell hangers
¾” bell hanger
Sink sprayer (from an old sink)
Add-a-valve fitting (Watts part #BPAV-666)
â” compression nuts (Watts part # A-104)
â” OD to ½” FIP reducing fitting (Watts part # A-118)
½” swing valve
½” check valve
½” FIP to â” FIP reducing fitting (Watts part # A-828)
¼” close nipple (Watts part # A-740)
2 feet of polyethylene tubing, â” OD, ¼” ID

The tools I needed for this project are
Channel lock pliers
Adjustable wrench
Phillips head screwdriver
Drill
Drill bits
Utility knife or tubing cutter
Cutting Pliers
Pipe Tape

Step 2: Begin Assembly

Slide the compression nut onto one end of the poly tubing with the threaded end of the nut facing out.
Push the insert into the poly tubing.
Tighten the compression nut onto the â” to ½” adapter.

Step 3: Assembly Continues

Wrap pipe tape around one end of the ½” nipple and screw it into the adapter. I used Schedule 80 PVC nipples which are approved for potable cold water in my area, but not approved everywhere, so check with your local building code office.
Wrap pipe tape around the other end of the nipple and screw the check valve onto that. The check valve is designed to ensure that water only flows one direction, so make sure you install it facing the right way. There is an arrow on the check valve pointing the direction the water should flow.
Use the second nipple and pipe tape the same way to connect the isolation valve to the assembly. I had to use the cutting pliers to cut the label off of my valve.
Use the third nipple and pipe tape to connect the ½” to ¼” adapter.

Step 4: Final Assembly and Mounting to the Wall

Wrap pipe tape around one end of the ¼” nipple and attach that to the assembly.
Wrap pipe tape around the other end of the nipple and add the sink sprayer.
Go into your bathroom and figure out your mounting location. My bathroom walls are made of wood so I just used screws to mount the hangers. If your wall is made of another material, use appropriate anchors. Feel free to tuck a bit of the sprayer assembly behind the bowl or tank, but be sure that you have easy access to both the valve and the sprayer handle.
Using a pencil, mark the location of the input side of the valve and the output side of the check valve.
Drill pilot holes for the two 1” bell hangers at your marked locations.
Open the bell hangers so that they are in an S-shape.
Screw the opened bell hangers into the pilot holes.
Holding your sprayer assembly onto the hanger bases, rotate the front half of the hanger into place.
Using the screwdriver, tighten the bell hanger to hold the assembly in place.
Use the ¾” bell hanger to mount the sprayer handle.

Step 5: Tapping Into the Toilet

Turn off the supply valve to the toilet.
Flush the toilet to drain the tank. Hold the flush handle open until the tank is as empty as possible.
Disconnect the toilet supply line from the valve. You may need to use a pair of channel lock pliers to do this, but be gentle if you do.
Install the T fitting on the valve.
Have a towel handy, the water in the supply line will drip onto the floor, but it's only a few ounces.
Install the toilet supply line on one of the other legs of the T.
Slide the compression nut onto the free end of the poly tubing with the threaded end of the nut facing away from your sprayer assembly.
Push the insert into the poly tubing. Tighten the poly tubing from your sprayer assembly onto the third leg of the T.
Turn on the toilet supply valve.
Check for leaks & tighten any leaky connections.