How to Install a Toilet

by A Manly Guest Contributor on February 6, 2013 · 31 comments

in DIY Home Maintenance, Manly Skills


Editor’s note: This is a guest post from Ethan Hagan of One Project Closer. Check out some of his other manly contributions like Making Your Own Cribbage Board.

Is your toilet cracked or damaged? Did your kid flush something that’s blocking the line? Are you looking to upgrade your commode? There are plenty of reasons for installing a toilet, and many homeowners call in a plumber to get it done. However, if you’re reasonably handy, consider trying this one yourself and saving a few bucks. Installing a toilet is a great DIY project, and just imagine the sense of accomplishment (and relief) when you finish. This tutorial will walk you through it step-by-step.


Tools & Materials

Installing a toilet doesn’t require much in the way of tools, and in fact, you can accomplish the task without any power tools. Here’s what you’ll need before getting started:

  • Toilet - plumbers I’ve spoken with say Gerber makes the best toilets, and they don’t recommend anything less than 1.6 gallons per flush.


  • Wax ring - if the flange sits even with or slightly below the floor, get an extended-height wax ring.


  • Closet bolts - self-adjusting closet bolts mean you won’t need to cut or snap the excess bolt length. Unfortunately, the local DIY center may not carry these, so check a plumbing supply shop.


  • Toilet connector - flexible, braided steel connectors eliminate using a tubing bender to fit the supply line between the stop-valve and the tank fitting.
  • Pennies or stainless steel washers - for shimming the toilet.
  • Torpedo level
  • Adjustable wrench
  • Screwdriver


I like to assemble the toilet before installing. The tank adds a little more weight but it’s much more convenient in my opinion. If you prefer, you can attach the tank afterwards.


Most manufacturers include all the necessary hardware and often install the fill-kit too. Double-check everything to make sure it’s right, and be careful not to over-tighten the nuts, which will crack the porcelain.


Step 1: Prepare the Flange

After you remove the old toilet, scrape away the nasty, old wax ring with some cardboard or something you can throw away. Inspect the flange, and if it’s cracked or damaged, repair kits are available at your local DIY center. For those up to the task, you can replace your flange without too much difficulty, but that’s outside the scope of this tutorial.


Step 2: Position Closet Bolts

Using self-adjusting closet bolts is the way to go because they eliminate the need to snap or cut excess bolt length. These bolts feature a white threadlocker that, when the hex nut reaches it, drives the stud further into the anchor nut.


Slip the closet bolts on either side and move the lock washers down snug against the flange.


Step 3: Place Wax Ring

You can put the wax ring directly on the flange or on the underside of the toilet. I opt for putting it on the flange because there’s no chance it’ll fall off when I’m lugging the toilet around.


If your flange is sitting a little low, use an extended-height wax ring.


Step 4: Set Toilet

Move the toilet over the flange and line up the holes with the closet bolts.


When it’s in position, firmly press the toilet against the floor.


Step 5: Add Washers and Nuts

Put the nylon washers and regular washers over the bolts and hand-tighten the nuts on both sides.


Step 6: Level the Toilet

Check the toilet for level front-to-back and side-to-side.


If it’s out of level or rocks back and forth, shim the toilet with pennies or stainless steel washers. You can buy plastic toilet shims; however, I’d advise against them because they often crack when I attempt to cut them to size.


When you’re satisfied that the toilet is level, tuck the pennies underneath the edge and out of sight. Next, tighten the nuts on the closet bolts, but not too tight. Attach the bolt caps to conceal the closet bolts.


Step 7: Attach Supply Line

Most toilets take a 3/8″ connector, and the connector I show here includes rubber gaskets that eliminate the need for wrapping threads with teflon tape.


Step 8: Verify Fill Level

When everything is connected, open the supply valve and let the tank fill up. Check for leaks and adjust the fill valve so that the water meets the fill line.


Step 9: Caulk the Base (Optional)

People are divided on whether or not to caulk the base of the toilet. The argument goes that caulking the entire base can result in leaks going undetected for some time. On the other hand, caulking the base can make for a more polished look. If you decide to caulk the base of the toilet, leave a gap or “weep hole” on the backside so you’ll find leaks sooner.


Ethan Hagan owns and operates a home improvement website called One Project Closer. On One Project Closer you’ll learn how to tackle projects with expert knowledge from professional contractors. OPC also provides coupons to home improvement centers, like this AJ Madison Coupons page. Check out OPC for full details, and follow them on Facebook.

{ 31 comments… read them below or add one }

1 Daniel February 6, 2013 at 4:16 pm

The wax rings easily get deformed while installing the toilet, and are a 1-time use item. I’d recommend using the adjustable, reusable toilet seals that use a rubber o-ring (“wax-free toilet bowl gasket”). They only cost a little more money and are much better. Plus, there’s no need for an ‘extended-height wax ring’, which you would not likely know you need until you’ve already returned from the hardware store with your new toilet. Do it right the first time and use a more modern technology: wax-free toilet toilet bowl gasket.

2 Mike February 6, 2013 at 5:14 pm

You know what’s easier to do when the toilet isn’t in the way? Cove base. ;)

3 Jeff R. February 6, 2013 at 5:17 pm

An equally handy and often overlooked step for the DIY remodel tutorial: how do you remove your old toilet AND the water that remains in the bowl!? Turning off the water and flushing only gets you so far. Great YouTube video to show you a very simply solution!

4 Steven February 6, 2013 at 5:34 pm

I found out the hard way that if your toilet isn’t already close to level then rocking it around on the wax ring will deform it and cause a leak.

The trick I learned was to test fit the toilet first without the wax ring. Get your shims in place (pennies? lol), glue them to the floor if you have to so they won’t move. Then you can take the toilet off, put the wax down and put it on without it rocking. Cut the excess shims off and it looks great.

5 Toby Barnett February 6, 2013 at 6:56 pm

Is the wax ring a one-time use piece? Like, if I screw it up and drop the toilet on the wax ring and deform it is that wax ring need to be replaced?

6 Gary Atcheson February 6, 2013 at 10:04 pm

I thought the note on 1.6 gpf (gallons per flush) deserved more comment. 1.28 is 20% less and has become more common to meet LEED requirements. For people interested in water savings, I would recommend paying a little more a dual-flush that has the option of using half the water depending on whether you are flushing solid or liquid waste.

7 Jon February 6, 2013 at 10:48 pm

I install toilets professionally and there are some things to do differently, in my opinion. Cedar shims are better than pennies because they are tapered, so you can adjust the toilet by pushing them in or out, are rot resistant, and all you need is a sharp utility knife to cut it to the the right length. An old putty knife is useful to remove old gasket and the new wax ring (I prefer wax over rubber for residential plumbing) should have a polypropylene sleeve to ensure a more positive seal. The youtube video posted by jeff was a neat trick, but I use a wet/dry shop vac to get ALL of the water out, and keep some cardboard around to put the old toilet on so you don’t mess up your floors when you put it down. If your flange is really loose, use wood screws to tighten it down or the toilet will rock no matter what you try. Happy renovations!

8 Kit Borden February 6, 2013 at 11:13 pm

Ha! Just did this the other weekend. Spot on instructions. I bought “composite” (plastic) shims because my kids’ toilet sits on a less than perfectly smooth tile floor, so I needed the extra height in a few places. I caulked because it hid the big enough to be noticeable gap. :)

9 Jason February 6, 2013 at 11:41 pm

I was always taught that the wax ring should be stuck onto the bottom of the toilet before setting, as opposed to putting the wax ring onto the flange.

10 Andrew February 7, 2013 at 12:38 am

Wow everyone is really beatting up this article. As a remodeling contractor I agree with most. One cool add on would be a supply line with built in safety valve. If the line bursts the valve shuts it off. Those suckers are small but through out a lot water if they break. Plus they tend to whip around like a little fire hose and make sure every surface gets equally drenched.

11 Matt February 7, 2013 at 6:25 am

I’ve done quite a few toilet replace/installs in my time due to my kids putting toys down the toilet. While this guide is good, there are a couple problems with it:

1. Wax seals, if large enough, ARE reusable. The problem is that the standard size wax seal is usually just barely big enough to seal the hole. Always buy the large size and you can reuse it.

2. NEVER use any metal item to shim a tank. They will corrode from the moisture inherent in a toilet area and leave stains on your floor. Worst case scenario the corrosion will leak out and stain the visible area of your floor. Cedar shims are better, but will decay. I recommend the new style of “snap off” plastic shims. available in a variety of colors, (usually tan though) they are inconspicuous and impervious to moisture.

12 sam February 7, 2013 at 6:37 am

“Next, tighten the nuts on the closet bolts, but not too tight”

This is a very important part. It turns out that it’s incredibly easy to crack the porcelain by over-tightening the nuts.

13 tim_lebsack February 7, 2013 at 8:16 am

Excellent article and a good skill to have. Too bad that we’re still using technology over half a century old for this.

14 Eric at A Lego a Day February 7, 2013 at 8:28 am

Thanks for posting this. This information will come in handy for me very soon! I have a toilet that needs to be replaced, and I’ve been afraid of doing it. Not any more!

15 Joseph February 7, 2013 at 8:53 am

Looks like that closet bolt package got ran over by a tank.

16 Adam February 7, 2013 at 9:55 am

I thought this was pretty good. However, one thing I’d add…putting straws from McDonald’s on the bolts makes it SOOO much easier to land the toilet right the first time.

17 Albers February 7, 2013 at 4:17 pm

And ready for use.

18 Rich February 7, 2013 at 6:59 pm

You forgot to mention to get new pennies made that year – so when the next person pulls up the toilet they know what year you put it in!

19 Rick February 7, 2013 at 8:28 pm

If the toilet is on a tile floor, I grout around the base of the toilet using the same color as the grout in the floor.

20 Splash Pitman February 7, 2013 at 10:38 pm

Australian plumber here , as advanced as you guys are I can’t believe you still use wax seals , looks like it has no adjustment in any direction , and to top if off the WC isn’t even flush with the wall .
When the floor is out of level I first put some masking tape on the floor around the base of the pan then put a wedge on a side or both sides at the back and one at the front , I pump silicon under the edge right around leaving the back until it is flush with the outside edge of the pan , then clean the edge up with your finger that had been dipped in soapy water , leave for 24 hours pull the front wedge out and silicon that hole and repeat the finger trick , with a sharp box cutter score between the masking tape and the pan and then remove tape , this stops the silicon going all over your tiles/timber floor .

21 Harvester February 8, 2013 at 10:44 am

Great article. I live in a colder climate and have found it helpful to use a small electric heater to get the bathroom, toilet, and wax seal up to at least 70 degrees F before installation.

22 Darden February 10, 2013 at 9:19 am

I learned the very hard way to get help in setting down the toilet and wear pants. I was installing a toilet a couple years ago and dropped the toilet while setting it down. The porcelain sheared off and cut 3 inches into my calf muscle = over 500 stitches. Freak accident but be careful.

23 bil February 10, 2013 at 12:09 pm

One trick I was taught is to make a slurry of plaster and squirt that under to toilet around the base from a cut plastic bag and straw. That stabilizes the base so the toilet won’t rock side to side. Esp. good for older uneven floors.

24 Craig February 10, 2013 at 3:20 pm

My flange has rusted to crumbs. I need a tutorial and how to replace it.

25 PJ Lewan February 19, 2013 at 12:28 pm

Nice article. I am a professional plumber and here are few other pointers:

The wax free seals are a great invention, however some old homes with very shallow or lead pipes underneath will be incompatable with them. Then you would use old school wax. If the flange is too far below the finish floor you can stack two wax rings together. Wear latex gloves when handling the toilet bowl wax as it is very sticky and gets everywhere. If you do have wax smears, solvent or wd-40 will aid in removal. Put the nasty old wax into the cardboard box that the new seal came in. Where I come from it is required by code to seal the base of the toilet with caulk. It keeps pee and toilet overflows from getting underneath and it helps ‘glue’ it down and keeps the toilet from coming loose. I would never use grout around the base of the toilet. It makes it extremely difficult to remove it for maintanence. Also I personally thing Gerber toilets suck. Try a Toto or American Standard. Enjoy!

26 Mike Z February 24, 2013 at 7:51 am

I was taught by a professional plumber to lay a bead of plumber’s putty on top of the wax ring when setting the toilet.

27 Brennan June 4, 2013 at 5:00 pm

Reusing a wax ring is a false economy. Value the labor you will put into redoing the job after cleaning up the sewage leak more than the six bucks for a new ring. In older homes with multiple layers on the floor the flange will further down than ideal, so a double stack of rings will work, one on the flange, one on the toilet and mush them down. Be sure the wax is above 70 degrees or it will not flow, it will crack and crumble like a candle and you will not get a good seal.

28 Amanda Peters June 11, 2013 at 3:08 pm

Love it! With articles like these, we can all make our husbands plumbers. :) Until they screw it up, and we actually have to call one…

JK. But seriously, great tips!

29 Charles Castell June 22, 2013 at 6:57 pm

Great stuff, all of this; I need to replace a toilet soon due to the tank cracking and creating a slight drip. One question: what is too tight, when all I have read says, “don’t over-tighten…”
At what point do I know when to stop with the wrench????

30 Bill Holder December 14, 2013 at 3:13 pm

Responding to Charles above – I’m not sure, but in one of these web articles I read “hand tight plus 1/4 turn”, so I’m going to give that a try and hope it’s tight enough. If not, I’ll try 1/4 turn at a time. Scared of cracking it.

31 Matt Naylor April 4, 2014 at 5:35 am

Nice post!! I think you have shared some great guidelines on how to install a toilet. Thanks for sharing!

Leave a Comment

Previous post:

Next post:

Site Meter