Convert Your Toilet to a Throne: How to Install a Bidet Toilet Seat [Video]

By Mengning Heil

April 22, 2022

Toilet Plumbing Tips

Reading Time: 5 minutes

Today, we’re going to learn how to install a bidet toilet seat. Let’s focus particularly on how to connect a bidet attachment to your water supply.  Click on the video, follow the steps outlined in the blog below the video, or use both to learn more.

I want to focus on this particular aspect because connecting the plumbing can be the trickiest part of a bidet toilet seat installation for the average homeowner.

As a master plumber, I was recently asked to help a homeowner who had successfully figured out how to install a bidet attachment. In other words, they were able to add a bidet toilet seat to their existing toilet, but they had trouble connecting the water to the bidet. 

Though connecting the water supply to the bidet is not difficult, it can seem a bit daunting if you’ve never done it before.  So let’s jump into this rather simple DIY project.

Prepare to Install a Bidet Toilet Seat

  1. What’ll you need:
    1. Towel
    2. Channel locks/wrench
    3. Bidet seat
    4. Toilet supply tube
    5. Bidet supply tube
    6. T-Fitting to connect the bidet and toilet supply tubes
  2. Locate your shut-off valves.
    1. Toilet shut off valve: Prior to working with your plumbing during a bidet toilet seat installation, you should first turn off the water. The shutoff valve is located behind the toilet. Turn the knob clockwise until snug. 
    2. Emergency shut off valve: It’s also good to know where your emergency water shut off is in case the toilet supply line or valve is leaking. 
  3. Confirm that the water is off.
    1. Next, test to make sure that the water is truly off. Remove the lid to the tank and flush the toilet, holding down the handle. 
    2. If the toilet tank does not refill with water after you flush, you know that you have successfully shut off the water.

Remove Toilet Water Supply Line

  1. Disconnect the old toilet water supply line.
    1. Place a towel underneath the toilet water supply valve.
    2. Disconnect the tube from the valve. Using a pair of channel locks, loosen the 3/8ths connector between the valve and the supply tube.
    3. Disconnect the tube from the toilet tank. Next, use your hand to loosen and disconnect the supply tube from the underside of the toilet tank. You should be able to pop it out by pulling it straight down once you have unscrewed the connector.
  2. Important: Never reuse the old toilet supply tube. Throw it away and replace it.

How to Install a Bidet Toilet Seat 

  1. Assemble the supply tubes.
    1. First, connect the T-fitting for the bidet to a new toilet supply tube. Snug it up by hand. Use a wrench or channel locks to tighten it further if the connection feels a bit loose. The gaskets should provide a reliable connection. 
    2. Connect the bidet seat supply tube to the T-fitting following the same process, snugging up the connection initially by hand and tightening as needed with a wrench or channel locks.
  2. Connect the supply tubes to the toilet and the bidet. (See video demonstration for clarification.)
    1. The large gasket at the end of the toilet supply tube should be connected to the toilet tank. Attach, twisting the gasket clockwise by hand until snug. Do not finish tightening this yet. (You will do this in step 7.4).  
    2. Connect the opposite end of the toilet supply tube to the toilet valve. Tighten with a wrench or channel locks until snug.
    3. Finally, connect the bidet seat supply tube to the bidet seat. Be careful to make sure the supply tube gasket (which is metal) catches correctly on the threads of the bidet seat (which is typically plastic).
      1. You should be able to turn the gasket several rotations by hand easily. If it gets tough turning it immediately, the threads may not have caught correctly. 
      2. Snug up the connection. Most bidet supply tubes come with a winged knob that fits over the connection between the bidet supply tube and the bidet. Use the knob to tighten the gasket, snugging up the connection a bit more.
    4. Finally, snug up the connection at the toilet tank, using a wrench or channel locks.
  3. Turn the water back on. Turn the shutoff valve knob (located behind the toilet) counter-clockwise a few rotations until you hear the water start to refill the tank.
  4. Check everything for leaks. If the valve leaks a bit, try tightening up the nut behind the valve knob.  Once you have checked for leaks and everything looks dry, you’re done!

Are you looking for an expert plumber in Damascus, MD or the surrounding areas? Heil Plumbing offers a range of reliable plumbing services, including drain cleaning in Rockville and water heater repair in Rockville.

Heil Plumbing is a family-run company owned by a third-generation master plumber. We can help you with a full range of plumbing services, including toilet installation and repair, leak detection and pipe repair, water heater repair and installation, faucet repair and installation, drain cleaning, water treatment services, and more.