I have a 1.6 gallon American Standard toilet that rocks a little from side to side. Upon closer examination, it looks like at least 1 (or both) of the anchor bolts are loose (they had corroded material under them and I can turn the bolt (not just the nut) so I'm convinced something is corroded.

enter image description here

I'd like to replace the bolts but I'm concerned that this is going to be opening a proverbial can of worms so I'd like to know what I'm getting myself into.

Specifically, I have two questions:

  • Where do these bolts attach to at the bottom? To the flange itself? Or directly to the subflooring?
  • What's the proper way to replace anchor bolts?
  • Plus 1. Sorry for the earlier post. I did some reading here about the purpose of StackExchange and concluded that your post was one that follows the guidelines. I was unaware that of the goal to provide an expert reference for problems such a yours, regardless of whether there are other cites that answer the question. – getterdun Mar 4 '14 at 12:44

The anchor bolts almost surely attach through the toilet flange. This diagram shows the general layout. (Click here for more detail.)

enter image description here

That image is part of U.S. Patent 7069603 showing who-knows-what. Here is what the flange and closet fitting have looked like in new construction for the last 20 years or so:

enter image description here

(photo uploaded by user "molo" and posted here.)

The six small holes are for fastening the flange to the flooring and indirectly to the subfloor. The two enlongated circular slots are for the heads of the bolts to slip under to fasten down the toilet. Shown with a new wax ring they should look like this:

enter image description here (posted by "adams444" here.)

Replacing these are simple in theory.

  • Buy a wax ring which are about $3. Buying two would not be overkill (see details further down for why). There are also kits with replacement anchor bolts for about that much again.
  • Give the toilet a few flushes to make the whole experience a little more pleasant.
  • Turn off the water.
  • Flush again and hold the handle to get as much water out of the tank as possible. Use a plunger to get most of the water out of the bowl.
  • Disconnect the water line from either under the tank or from the valve coupling.
  • If it is a two piece toilet, is heavy, and you don't have a helper, look inside the tank for a way to detach the tank from the base. Be prepared for a half gallon of water to splash out by having a bucket, towels, mop, etc. on hand. Otherwise prepare to lift the toilet as a single unit.
  • Remove the nuts from the anchor bolts.
  • Lift toilet mostly straight up. You may have to rock it side to side or front to back to overcome the wax ring's adhesion while lifting. To minimize water splashing on the floor, keep it tipped forward (away from the wall) and set it out of the way.
  • Assess the situation. Maybe you want to replace the flange, or even install one if the installation is really old. Most hardware stores sell kits with a flange, bolts, nuts, and wax ring for about $6. You'll have to make sure the pipe underneath is compatible with the new flange: if it is recent construction (~1980s and later), some ABS glue will be needed. If it is older, an ABS to cast iron coupling is needed (and maybe some pipe sawing).
  • Note that a modern flange is designed to go on top of the flooring which is meant to go all the way under the toilet.
  • Once the flange is good to go—be sure it is installed in the proper orientation so that the anchor bolts can go in the curved slots and through the toilet—measure how much bolt length is actually needed and break or cut them to length, install them, the wax ring, and set the toilet into position. To do this smoothly without experience, use two helpers: two to lift and position the toilet and one eyes on ground positioning the anchor bolts (they tend to tilt) and directing the other two.
  • Put the anchor nuts on, moderately tighten, and check if the toilet is loose. If the bolts are still too long, you might be able to hacksaw them with the toilet in position (put nuts on first so they can de-burr the thread at the cut). Otherwise, if you lift the toilet out again, it is best to install another new wax ring. (The squished new one makes a great shop item for waxing nails and screws for easier assembly.)
  • Reassemble and reconnect water line.

With everything ready to go, this is 60–90 minutes work. If everything goes wrong, it could take half a day.

The biggest danger is that once the toilet is off, you will see sub-floor (and maybe a floor joist) with dry rot and worse. Then you'll have to choose whether to just fix it up as best you can, or tear the floor up and replace everything that is wrong.

Good luck!

  • Could you add proper attribution for these images and ensure that they're not from competitive sites. Please see this meta discussion for more information. – Niall C. Mar 2 '14 at 3:59
  • @NiallC.: Attributions added. Is that good enough? – wallyk Mar 2 '14 at 4:35
  • @NiallC: Have deleted my earlier comments based on reading about this site's purpose: to provide expert information on home improvement problems regardless of whether other web sites cover the solution. Unfortunately, I cannot reverse my earlier vote. I'll check and see if there is a way to do that. – getterdun Mar 4 '14 at 12:49
  • 1
    Definitely consider buying two wax rings. I got away with an "oops", but really should have used a new ring. – keshlam Aug 31 '15 at 16:55
  • 1
    You may want to avoid getting the wax rings that have a rubber funnel inside of it. The funnel itself can get crimped and cause a blockage or divert the waste outside of the toilet flange if the toilet shifts. – Jason Hutchinson Sep 10 '15 at 13:57

There's a good chance the toilet flange is corroded as well or it's attachment is compromised.

The flange attaches to the structure and the bolts slide into the flange and nuts and washer hold toilet down.

You're going to need to drain the toilet and remove it. May need to cut the bolts if you can't get the nuts off.

Inspect the toilet flange and see if it's attached properly and doesn't move. If the flange needs to be replaced there are repair flanges like that are easy to install provided the wood under the toilet hasn't rotted in which case you'll need to repair that. The two slots on the side is where the bolts head go. The other holes are for screwing the flange down to the floor.

A wax ring creates a seal between the outflow of the toilet and the drain pipe. You're probably going to gag a little when you remove the old one cause, well it's gross and feels like dookie.

If the floor is not level they make these little plastic shims to slip under to keep it from rocking.

Since you're completely removing and reinstalling the toilet it's a good time to think if you want to replace it with a new one for any reason like getting a more efficient one or a heated one that spritzes you clean with Evian or something.

Don't over tighten the nuts or you may crack your crapper.


Two tips that may help:
A wet/dry shop vac may be used to get the water out of the bowl.
The easiest way to lift a toilet is to take a suitable rope or strap, and wrap it around the bottom front of the bowl, cross the ends at the base of the tank behind the seat, then go round the back of the base and tie the ends, or bring them back round to the front and tie them if it's easier. You should now have a figure 8, with one loop around the bottom of the bowl at the front, and the other under the tank. Straddle the bowl, grasp the rope where it crosses behind the seat, and lift. Most toilets will balance quite well if lifted this way, and it's much easier to lift the weight in this manner than trying to grasp the bowl or tank and trying to lift. Lifting in this way also works well when it's time to put the toilet back in place.


The nut may turn loose as bad as it looks. The bolt is usually brass on older installs so the nut will not fuse to the bolt. But if it is... Grab the exposed part of the bolt above the nut and loosen it enough to get about a 1/4" of space between the nut and the toilet. In this space cut the bolt just above the toilet base to remove the nut.

Remove the toilet after you have removed as much water as possible using the plunger first, then a bucket and sponge. This will still not get all of it but if you keep the toilet as level as possible, you won't make a watery mess. Have a trash bag handy to set the toilet in so it won't drip any where too.

To re install, you will see the bolts you cut off. They reside in a slot that is part of the pipe that the toilet sets on. New or old, the toilet flange is shaped the same way, just the materials have changed.

Image from www.plumbingsupply.com

The bolts are "T" shaped so they do not readily spin, although when corroded bad enough they will.

Image from Global Sources

There are notches that the bolts can fit into also, if the flange is situated for that install too. But the slots are what I have seen used most of the time.


I see some of the answers mention what has been going on in the plumbing industry for the last 20 years or more. There is a new solution that I came across recently that is pretty innovative and sets a precedent in the market.

Its called the Culwell Flange. This flange comes in 3, 4 and a 4x3 inch models in ABS and PVC. They offer glue in hub style, a compression fit and a drop fit styles to suit your needs.

Their claim is that they seal to the existing subfloor as a means to keep out any water that can get in and cause damage. I recently installed into a bathroom I was renovating for accessibility, that is how I came across these flanges.

I found mine on Amazon, but I believe they have a storefront way to purchase as well. Lots of videos on Youtube, and they have a pretty nice website

I would highly suggest looking into these flanges when you replace your flange on your commode. They cost more than the average flange, but their value seems to be invaluable. Replacing the flange seems to be the best answer here, and it is my experience that tells me that is your problem. Replacing is a pretty easy task, but does take a little bit of time and patience.


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