How to Install A Toilet Flange

how to install a toilet flange

Replacing a toilet flange can be intimidating the first time. But generally remains one of the simplest home repairs on how to install a toilet flange. Over time, the wax ring that connects the flange to the bottom of the toilet may become compromised. A new ring and flange are essential to securing a proper seal.

The easiest way to tell if you need to replace the flange is to see if your toilet leaks water between the base and the floor of the bathroom when you flush it. While this leak can come from cracks in the porcelain toilet or other piping, it is most likely an issue with the flange.

Step By Step On How To Install A Toilet Flange

how to install a toilet flange for DIY

We’ll be walking through how to install a toilet flange, step by step. For this repair, you’ll need a new toilet flange, a wax ring, and tools to unscrew your toilet and flange from the floor. We also highly recommend gloves for this specific procedure, as to reduce the risk of infection and out of personal sanitation needs.

A gas mask may be required for those particularly sensitive to sewage odors, so take necessary precaution if you find yourself worried about the smell. Chances are, the stench will be worse than you initially realize.

Removing The Old Flange

Before we remove the old flange, we’ll need to get the toilet out of the way.

Disconnect The Water Line

disconnect the water supply on how to install a toilet flange

To do this, first, disconnect the water line from the toilet. This is usually found on the underside of the tank, either on the left or the right side. You will need to both disconnect the water supply by closing the valve, and then disconnect the hose from the toilet entirely.

Be careful as you do this—since water in the tank can easily pour out of the open water supply in some models. To be safe, turn off the water, then flush the toilet until no water remains in the tank. Then, remove the water supply from the underside of the tank.

Remove The Caps

remove the lid on how to install a toilet flange

Next, remove the caps on the left and right side of the bowl. And carefully unscrew the toilet from the ground. Remove the tank lid before removing the toilet. As this can easily slip when removing from the ground.

Remember that some residual water may remain in the bowl, even after flushing the water from the tank. Try to remove this water with a wet & dry vacuum. Next, remove the toilet and place it out of the way, using a friend to assist you if possible.

The old flange should be secured to the ground and coating in old wax. Once you remove the toilet and break the wax seal, the sewage smell may begin to leak upwards. If necessary, cover the sewage opening with a towel—being careful to choose one that will not fall into the sewage pipe itself.

Remove The Wax

Next, use a dull knife or putty knife to start removing the wax from the old flange. Even though we’ll be replacing the flange entirely, getting the old wax removed from every crevice of the sewage opening is important to ensure a proper seal.

Remember also to check the underside of the toilet for excess wax. Both the porcelain surface and the sewage opening need to be as clean as possible for the new flange.

Finally, unscrew the flange from the sewage opening, and remove any wax that remained underneath the flange. Then, clean the floor underneath the toilet to remove any discoloration differences between the floor underneath the toilet and outside of it.

Installing The New Flange

When learning how to install a toilet flange Installing the new flange is essentially performing the same process in reverse; it will take a bit of extra work to make sure everything remains in the proper location.

How To Install A Toilet Flange With A New Flange

First, make sure that the new flange is the exact size of the old one. You may want to hold off on purchasing a new flange and wax ring until you can bring the old one into a hardware store to compare. For the sake of others, however, clean the old flange as best you can before heading to the store with it.

Clean off the openings and screw down the new flange. Most new flanges come with their screws, so be sure not to reuse older screws that may be stripped of their threads. New flanges also need to be rotated into position, so make sure you’ve properly secured your new flange based on the instructions given.

Open And Unwrap The Wax Ring

Next, open and carefully unwrap the wax ring. For most wax rings, you’ll be first pressing into the bottom of the toilet, then pressing the toilet onto the flange. Make sure of this by reading the instructions given with the wax ring, and perform in the order given.

Since the wax ring is naturally adhesive, you shouldn’t need to do anything specific to the underside of the toilet to ensure a proper seal. Just make sure that the ring lines up precisely with the opening on the underside of the toilet.

Press Down The Toilet On The Flange

Next is the most difficult section of the installation. The wax is malleable, and will naturally form based on how you press down on the flange. Likewise, misaligning the toilet and needing to lift up to realign will greatly compromise the integrity of the seal, and force you to start all the way from the beginning.

If possible, get a friend or a family member to lift up the toilet with you after securing the wax ring. Using one person on each side, make sure that the toilet is lowered gently and threaded with each bolt on the left and right sides. If you haven’t removed your towel from the opening of the sewage pipe, now is the time to do so.

Seal The Toilet To The Flange

seal the toilet to the flange on how to install a toilet flange

Try not to pay attention to any footprint or discoloration on the ground, but rather focus on the bolts alone. It is not unusual for a new flange to shift the footprint of the toilet slightly.

Once lowered onto the ground, press directly down to properly seal the toilet to the flange. Sitting on the toilet is effective, but make sure you also press down where the tank is situated to make sure your seal isn’t more effective towards the front of the toilet.

Double-checking Your Handiwork

Next, we’ll need to set the toilet back up.

Screwing the toilet back onto the ground might sound like the easiest portion of the repair. But it is often where most people cause damage to the toilet. The porcelain on most toilets is fragile, so you will need to tighten the bolts carefully.

Once you’ve tightened the nut to the surface of the porcelain, only give another turn or half turn to secure the toilet fully. Remember that you can always tighten the bolt later on, but if you tighten the bolt too much now, you may crack your toilet and have to repeat the process at great expense.

Secure The Caps

Once secured, place the caps back on the bolts and move next to the water supply. Reinstallation of the water supply to the underside of the tank shouldn’t be a problem, but make sure that the threads on both the toilet and the hose are properly cleaned. Leakage here after a flange replacement is common for those who do not make sure they’ve cleaned both surfaces.

After securing, open the valve and allow the tank to fill up completely before testing your toilet. Once it is full, flush the toilet at least three times and watch where the toilet connects to the ground. Provided you followed the steps precisely, there should be no leakage.

Place The Lid Of The Tank

cover back the lid on how to install a toilet flange

After this, you’ve finished! Simply place the lid of the tank back onto the toilet and begin the process of cleaning up. Flanges and wax rings can be thrown away into the regular garbage. But it is probably best to double bag these items to prevent infection.

A leaking toilet might seem like a cause for a plumber. But replacing the flange yourself will solve the issue most of the time. If you’ve followed these steps precisely on how to install a toilet flange. You will either determine that the leak was the flange, or that a more serious issue is occurring.

Purchase The Right Flange

Flanges are relatively cheap and can be purchased from most hardware stores. These will often come with the wax rings included. If you’re not sure, ask your local hardware store employee and make sure you have the ring with you.

So long as you can move past the smell and feel comfortable lifting a toilet. There’s no need for extra help when going through the steps of how to install a toilet flange. The entire process should take under an hour and can save hundreds when compared to the work of a plumber.


  1. What a fantastic article. This is so chock full of useful information about installing toilet flange. Great extra tips and ways, I simply wished you many thanks.

  2. Great article, good step by step instructions. I would add that flushing the toilet during replacement of thetoilet wax ring a few times before starting, if possible, is a good idea. This will help drive any sitting waste further down the drain. Thanks for this well put together article!

Leave a comment

Your email address will not be published. Required fields are marked *