I'm Ricky Cox, master plumber with Sewer Studs Plumbing & Drain. A toilet that rocks is not a small annoyance. Every rock works the wax seal loose, and a loose seal is how water ends up under your floor. In this video the customer complained the toilet was wobbling, and the closet bolts were completely broken off — which told me there was more than likely a broken closet flange underneath.

It turned out the flange wasn't broken at all. What was broken was the last install. Here's the whole job, step by step.

Step One: Pull the Toilet and Look at the Flange

First, turn the water off, disconnect the supply line, vacuum the water out of the tank and the bowl with a shop vac, and lift the toilet straight up and set it in the tub. I get right over the toilet and squat it up, hands under the edge of the seat, center my weight, and lift straight.

Two things showed up right away on this job:

The angle stop was toast. The supply line wouldn't turn off because the angle stop wouldn't close, and it was dripping — so the angle stop and the supply line got replaced as part of this job.
The old wax ring had been leaking for a while. You could tell by the buildup and the stains where water had been escaping under the toilet.

Step Two: Replace the Angle Stop With a Quarter-Turn Valve

The old angle stop comes off and a brand-new quarter-turn stop goes on — quarter-turn means it's either on or off, with a ball inside, so you don't get this failure again.

On this job the pipe is copper with a male adapter soldered on the end, so the swap is unthread the old stop, thread the new one on:

Clean any excess old Teflon tape off the pipe.
Wrap new Teflon tape clockwise, about five to six times, then add pipe dope.
Thread the new valve on, and always put a backup wrench on the other side so you don't risk snapping the pipe or causing damage while you're turning it.

Then the new supply line hooks right up to the valve, ready to go directly onto the toilet.

Step Three: Check the Flange Before You Replace It

Once the valve is done, look hard at the flange before you decide it needs replacing. On this one:

The flange itself was not in terrible shape and sat pretty close to level with the floor.
There were no breaks in it.
The real problem was the way the closet bolts had been anchored last time — they hadn't been anchored properly at all, and extra grout applied around the flange was preventing the bolts from getting in and grabbing the existing flange.

So instead of installing a new flange, I chiseled that grout out with a hammer and a flat chisel, scraped the debris off the flange so the wax ring would seal clean, and reused the existing flange. If your flange actually is broken or spinning its bolts, that's a different repair — our PVC toilet flange replacement guide walks through cutting the old flange out and gluing in a new one.

Step Four: Anchor the Closet Bolts to the Flange

This is the step the last installer skipped, and it's the step that makes the fix permanent. If you don't anchor your closet bolts to your flange, you risk the bolts moving, getting out of the flange, or even breaking — and the toilet rocks again.

Here's how I anchor them:

Set the closet bolt into the flange, wide side against the flange so it has greater surface area to grip.
Put a flat washer down over it.
Run an acorn nut down with its flat side against the washer to anchor the bolt to the flange.
Get it hand-tight, then crank it with two pairs of pliers. You'll feel it get tight — that bolt isn't going anywhere.

Do the same on the other side, chiseling out a little more grout if the bolt won't seat all the way. I buy closet bolt sets with two sets of washers and nuts for exactly this reason: one set anchors the bolt to the flange, the other set bolts the toilet down.

Before the reset, clean the whole area up: scrape the old caulk line and the leak stains with a putty knife, wipe it down with rags, and sanitize the floor where water was escaping under the toilet.

Step Five: Reset the Toilet on a New Wax Ring

Set a new wax ring centered right on the flange. I use a plain wax ring — I'm not a fan of wax rings with horns; I've seen them get really nasty if there's a stoppage.

Then line yourself up with the bolt holes on the side of the toilet, lift straight, look down the toilet as you set it, and let it come down slowly, directly onto the wax ring.

Step Six: Shim It — Because the Floor Is the Real Problem

The second this toilet was set, it was clear the floor was extremely unlevel. There was a massive gap underneath one side of the toilet — and that gap is why it was wobbly.

If you don't shim or grout a toilet on a floor like this, it will rock. Period.

Check the toilet with a torpedo level and figure out which way it wants to lean.
Insert shims under the low side — on this job, the left side first, then the front, doubling the shims up where the gap was biggest.
Test the wobble before you bolt anything down. A little bit of shimming fixes a lot of wobble — by the time the shims were in, this toilet wasn't going anywhere, and it hadn't even been bolted yet.

Step Seven: Bolt It Down — Snug, Never Cranked

Put the china cap bases down first, the side that snaps in facing down so it adheres well.
On top of each cap base: a flat washer, then an acorn nut with the rounded side facing down, which centers the washer and gets everything nice and tight.
Hand-tighten both sides evenly, then tighten a little more with a small pair of pliers.
Don't overtighten your closet bolts. Snug is the goal; cranking on porcelain is how bowls crack.

Hook the supply line back up to the toilet, turn the water on, and flush it a few times to check for leaks. On this job: no leaks at the new angle stop, the new supply line, or the base.

Step Eight: Cut the Shims and Grout the Base

Run a razor blade right alongside the edge of the toilet and cut the shims flush.
Pop the trim caps on over the bolts.
Flush-test a few more times.
Grout around the base. With premixed white grout and a putty knife, push the grout thick underneath the toilet — especially in the areas where there's a big gap — all the way around the base, then clean it up with a grout sponge, going around the toilet a few times and rinsing as you go.
Let the toilet sit overnight with the grout, so it's got something real sturdy to sit on.

That grout isn't decoration. On a floor this far out of level, the shims level the toilet and the grout locks that level in.

Why a Rocking Toilet Shouldn't Wait

A rocking toilet isn't just annoying — every rock works against the wax seal, and this one had already been leaking under the bowl long enough to leave buildup and stains on the floor. Catch it early and the fix is bolts, shims, and grout. Let it leak, and you're into floor damage. The same pull-and-inspect approach shows up in real jobs in our toilet pull and reset vlog from Carrollwood, and if your toilet's problem is the flush itself, our pressure-assist cartridge guide covers that fix.

Thinking About Toilet Work at Your House?

A pull-and-reset like this one is one piece of toilet work. Our fixture installation page covers how we handle toilet installs and the change-order items that can surface once a toilet is pulled — the flange, the bolts, and the wax ring are exactly that kind of item. If the problem is smaller — a running toilet, a flush that isn't right — start with small plumbing repairs. We serve homeowners across Tampa Bay — see our Tampa plumber page.

Frequently Asked Questions

Does a rocking toilet always mean the flange is broken?

No. On this job the closet bolts were broken off and I expected a broken flange — but the flange had no breaks and sat close to level. The bolts had never been anchored to it properly, and grout around the flange was keeping new bolts from grabbing it. Chiseling the grout out and anchoring new bolts to the existing flange fixed it.

Why anchor the closet bolts to the flange instead of just dropping them in?

If you don't anchor your closet bolts to the flange, the bolts can move, slip out of the flange, or break — and the toilet starts rocking again. Anchoring each bolt with a washer and an acorn nut, flat side down and cranked tight with two pairs of pliers, locks the bolt to the flange before the toilet ever goes on.

Why did this toilet need shims and grout?

Because the floor was extremely unlevel, with a massive gap under one side of the toilet. Shims under the low side leveled it, and grout pushed thick around the base locked it in. On a floor like that, an unshimmed toilet will rock no matter how tight the bolts are.

Do you reuse the wax ring when you reset a toilet?

No. This reset went on a new wax ring — a plain ring, centered on the flange. I don't use wax rings with horns; I've seen them get really nasty if there's a stoppage.

The shutoff valve behind my toilet won't turn off. Is that part of the same job?

It was on this one. The angle stop wouldn't close and was dripping, so it was replaced with a new quarter-turn valve and a new supply line while the toilet was pulled — Teflon tape and pipe dope on the threads, and a backup wrench on the pipe while the valve was tightened.

Ready to Talk About Your Toilet?

If your toilet rocks, wobbles, or leaks at the base, we'll give you a straight answer and a firm quote. Call Sewer Studs Plumbing & Drain at (813) 680-2284, Monday through Friday, 8 AM to 5 PM.

Fix a Rocking, Wobbly Toilet: Anchor the Closet Bolts, Shim It Level, Grout the Base