A Rocking Toilet Could Be a Sign of a Much Bigger Problem

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While sitting on a rocking chair is relaxing and soothing, sitting on a rocking toilet tends to have the opposite effect. As it turns out, making contact with the toilet seat while simultaneously feeling the entire porcelain fixture shift beneath you is not only unsettling—it could also be the sign of a much larger plumbing problem.

Although there are some DIY fixes for a wobbling toilet, establishing a solid connection between the base of the toilet and the floor without looking into what's causing it to rock in the first place, may end up masking other more serious issues. Lifehacker enlisted the help of three plumbers and a general contractor to walk us through some of the most common causes of a rocking or wobbling toilet, potential DIY repairs, and why it's so important to address the problem right away.

Why is my toilet wobbling?

There are three key parts to a good connection between the base of the toilet and the sewer line it feeds into, says Roy Barnes, a plumber with roughly 30 years of experience, and the co-owner of Service Force Plumbing in Rockville, Maryland. They are:

The flange: The wide ring at the top of the sewer line, where it comes up to the floor. It has holes for the bolts, and also helps create an effective seal. "These flanges can deteriorate with age and should be inspected if there are problems," Barnes tells Lifehacker.

The wax ring: Creates the actual airtight and watertight seal between the porcelain toilet and the PVC or metal sewer drain. In addition to holding the toilet down, the bolts at the base of the toilet also keep the wax ring firmly in place, making it airtight and watertight.

The base of the toilet: Must be sound, without hairline cracks or age-related wear.

When one or more of these parts is compromised, it could result in a rocking or wobbling toilet. More specifically, Josh Rudin, a general contractor and the owner of ASAP Restoration, a water, fire, and mold restoration company in Phoenix, says that some of the most common reasons why a toilet is rocking include:

Loose toilet bolts

Damaged wax rings

Uneven flooring

Uneven or damaged sub-flooring

Loose flange fitting

Improper positioning

Cracked toilet base

While any of those issues could leave your toilet unstable, the bigger question is what, exactly, caused the loose bolts or damaged wax ring?

According to Barnes, one of the most common causes of these problems is a botched bathroom renovation that includes having a new floor put down. "It is very important that the flange of the sewer pipe be flush with the level of the floor, but too many flooring contractors don't know this," he explains. "They lay the new floor at an incorrect height for the existing flange, and then when the toilet is reinstalled, the wax ring doesn't make a correct seal."

Homeowners often don't discover this problem until their toilet starts to rock, months or years after the renovation, says Barnes. It's only then, when they hire a plumber to deal with the wobbling toilet, that the homeowner learns that the seal had been leaking the whole time and caused significant damage to the subfloor.

How to figure out why your toilet is wobbling

Whether you're going to attempt to fix your rocking toilet yourself or hire a plumber, it would be helpful to look for and make note of certain signs that could help explain what's causing the fixture to wobble.

Kodi Wilson, a plumber, plumbing instructor, and campus director of National Technical Institute's Las Vegas location, suggests starting off by inspecting the bathroom to see if you're able to visibly identify the issue. "Many of these things you can tell just by looking at a toilet, and many of these [problems] will occur together, depending on the root issue," he tells Lifehacker. "Has there been a leak? Does the floor show signs of damage? Are the nuts and bolts loose to the touch?"

Water leaking from the base of the toilet probably means that you have multiple problems on your hands, Wilson says, adding that "the best thing to do is remove the toilet and determine the amount of damage."

Look for signs of damage on your flooring. According to Wilson, there are two common causes of warping, and uneven, popping, or cracking tiles: Water damage and the settling or aging of the home. Again, if you notice this type of damage on your floor, he recommends having the toilet removed and determining the cause.

If you notice that the bolts connect the base of the toilet to the floor are loose, don't assume that you simply need to tighten them and then everything will be fixed. Instead, immediately double check for water damage, Wilson advises.

Barnes agrees, noting that while it's possible that tightening the bolts will solve the rocking problem, you should never make that assumption. "First, if the toilet has been rocking for a while, the simple repeated motion could have caused a failure of the wax ring seal and allowed water to leak out of sight," he explains. "Not only is this potential damage bad by itself, but if simply tightening the bolts makes everything 'feel' solid, it could be hiding water that continues to leak and damage the subfloor and joists."

In addition to looking for potential signs and causes of toilet problems, Rudin suggests following your nose. “A compromised seal can also lead to unpleasant odors emerging from the sewer system, and the rocking of the base unit can force them to emerge,” he says.

Why you should never ignore a rocking toilet

As the experts have noted, there's a good chance that a wobbling toilet is a symptom of much larger—and more expensive—problems.

In the short term, the instability of the toilet can lead to leaks around the base, potentially causing water damage to the floor and subfloor, says Matt Kunz, president of Mr. Rooter Plumbing, a subsidiary of Neighborly, a service-based franchise company. It can also create an uncomfortable, nerve-racking, and potentially unsafe toilet experience for the members of the household and their guests.

"In the long term, persistent rocking may compromise the wax ring seal and the toilet's connection to the floor, increasing the risk of more extensive water damage," Kunz tells Lifehacker. "Addressing the issue promptly ensures a stable and secure toilet, preventing potential structural damage, and maintaining proper functionality in the bathroom."

Plus, if there is some type of water damage, it could also lead to mold growth, says Wilson.

Lastly, as Rudin points out, the longer a problem involving water leaks and damage is left to linger, the worse and costlier it will get—both in terms of the repairs themselves, as well as the negative impact of the damage on your property value.

How to fix a wobbling toilet

Technically, there are DIY methods for stabilizing a toilet, but as the experts have already explained, these only stop the rocking and don't address any of the potential underlying issues. “There are no easy fixes for a DIYer doing a toilet base fix on their own,” says Rudin. “Most toilet jobs are two-person affairs, simply because a toilet can weigh 100 pounds or more, depending on the model.”

However, if you're 100 percent confident that you've discovered the root issue, and there are no signs of water damage, Wilson says that it's possible to stop the toilet from wobbling in one of two ways. The first is tightening any loose bolts on the base of the toilet—ensuring that they're all even, and without over-tightening them, which Wilson says can crack the porcelain. If you can see the floor has settled with time but there is no water damage, Wilson suggests the second method: Shimming the low side of the toilet and tightening the bolts.

Before attempting any of that, Barnes says that it's first essential to verify that the flange and the wax ring are in good shape and doing their part to prevent leakage. But even if they are, when you attempt to stabilize a toilet on your own, you always run the risk of ignoring and then hiding the larger problem. "Keep in mind that the connection between the flange, wax ring, and toilet works extremely well if installed properly," he explains. "So, if you need to shim the toilet to stabilize it, it is more than likely that it was not installed properly, or that some part of the installation has failed."

When to call a plumber

Fixing a rocking toilet isn't as simple or straightforward as it sounds. Given all the potential complications, in most cases, it's probably worth paying for a plumber to come take a look, rather than shelling out for pricey repairs for undiscovered problems down the line. Or, as Barnes puts it: “Installing a flange at a proper height and a wax ring correctly sized for the job is far less expensive than tearing out and replacing subfloor, flooring, and even flooring joists in the worst case, a few years down the road, when far more damage has occurred.”

There's also the possibility of you inadvertently causing additional damage while attempting to fix a wobbling toilet on your own, making the whole project more expensive for a plumber to fix. “That might ultimately amount to thousands of dollars in damage in the long run,” Rudin says.