Reasons Why Your Toilet May Keep Clogging

Toilet blockages can occur for many reasons, some more obvious than others. That said, the most common causes of clogged toilets can be boiled down to one of seven possible issues: mechanical malfunctions, like a faulty flapper; structural blockages with the trap or vent; damaged sewer lines; old low-flow toilet models; someone flushing things that aren't meant to be flushed; excessive paper usage; and limescale buildup.

Depending on the severity, you can remedy some of these root causes on your own (though it's never a bad idea to call for assistance anyway). That said, some clogs will demand more impressive and professional means — like a seasoned plumber with a snake or a roto-rooter. In the worst-case scenario, if clogging seems to be a routine occurrence, and a plunger, liquid drain cleaner, or snake aren't effective, your plumber might need to do a more in-depth visual diagnosis by taking live video footage using a sewer line camera. Below, we'll explain in detail the various reasons these obstructions occur, and you'll learn how to fix a toilet that keeps clogging up depending on the root cause behind the blockage. 

If your toilet is clogged but seems to be running continuously, your problem might be as simple as a faulty or deteriorating flapper. Its function is to let water out when you flush and then stop water from draining so that the tank can fill up. If the flapper is worn out, damaged, or not fitting correctly, you may not have enough water in the toilet tank to flush properly. Insufficient water flow means clogs may become a more frequent occurrence.

The resolution is simple: Get a new flapper valve and install it yourself. To make sure the new part fits, take the old one to a hardware store and ask an associate to help you find the same type of toilet flapper. Once you're ready to install, turn off the toilet supply water and hold the flush lever until the tank is empty. Clip the new flapper onto the chain attached to the flush valve. The chain won't work correctly if it's too loose or has too much tension, so you may have to adjust it. Once you've installed the replacement flapper, turn the water back on and run a test flush.

A plumbing vent has a very important job — it keeps various gasses and smells from entering your home. It also helps regulate air pressure in the piping, which allows your toilet to get a nice, full flush. But its location leaves it vulnerable to blockages. That's because the piping leading to the vent goes directly through the roof of the house, where it's exposed to the elements, flying debris, and even sheltering animals. If a blockage forms in the vent, the toilet will produce much weaker flushes because of insufficient air displacement. Fix the issue by cleaning the vent or getting a professional to do this for you.

Another common blockage concerns the toilet trap — a P-shaped integral pipe located between the bowl and the drainpipe, the sole purpose of which is to prevent sewer smells from backing up from the toilet bowl. A lack of water and pressure stemming from mechanical or external forces can cause easily flushable items to become blocked in this trap. You can clean the toilet trap with a nice, strong plunge to release the blockage. Failing that, call a professional.

Sometimes clogs have absolutely nothing to do with your toilet and everything to do with sewer line issues. Your main sewer line — the network of piping that takes all of the wastewater out of your home and to the municipal sewer line — can get blocked by any number of external factors. Bad plumbing connections, old or damaged piping, and tree roots in particular are common causes of clogging because they inhibit your plumbing system's ability to remove waste from the home. 

It's relatively easy to figure out if your main sewer line is the culprit. If plunging your toilet (or sink) is becoming part of your everyday routine, everything smells and drains slowly, and your yard has become a stinky, boggy mess, you've got a sewer line clog. A clogged sewer line needs to be dealt with right away to avert a dangerous sewage backup. Calling in a professional plumber is your best bet in this situation, since the fix involve extensive diagnostics and invasive repair methods — the old pipes may have to be broken apart and replaced. Since this issue is caused by unruly tree roots, you can prevent it in the future by only planting trees that won't damage your water and sewer lines.

If your toilet is prone to clogging, and you have a first-generation eco-toilet, this could be the issue. These low-flow bathroom fixtures were first brought on the market in the early 1990s, when the United States passed a law mandating that toilets made after 1992 couldn't using more than 1.6 gallons per flush. It's been many decades since, and modern-day conservation toilets have more flushing power while using even less water.

If your aging low-flow loo tends to get overwhelmed, you might want to try swapping out the float for a different version or adjusting its setting so more water fills the tank. The float is located in the tank and attaches to the fill valve. Once you flush, the float begins to rise with the water level. If it's broken, obstructed, or set too low, you'll get a weaker flush and face potential clogs. If this doesn't help, upgrade the toilet to a modern low-flow, dual flush version. 

Routine toilet paper use can lead to clogs if you're flushing too much paper at a time. Toilet paper is specifically designed to dissolve in water, which is why it's okay to discard it in the bowl before flushing. That said, forcing the toilet to process copious amounts of it in a single "sitting" translates into longer disintegration times. Once flushed, the pulpy mass can clog the toilet (or the sewer lines downstream), preventing it from flushing normally — and often leaving you with a mess of the unspeakable on the bathroom floor. Unfortunately, hoping that the blockage will self-destruct over time is a fool's errand. Like a snowball, the clog will only grow with every flush, and you'll risk having a hazardous — not to mention incredibly foul — sewage backup in your home. 

Not all toilet paper types dissolve as quickly as you'd want them to, either. Thicker tissue, while quite forgiving on the sensitive body parts it grazes, takes a while to disintegrate in water. This extra time enables it to accumulate inside the pipework. 

So, how much toilet paper is too much? Most people use fewer than 10 squares per flush, and toilets can generally handle twice this amount. However, much is down to individual preference, so as long as you're reasonable and the TP doesn't feel like an oven mitt on your hand, you're probably fine. If you use thick toilet paper, be extra cautious and significantly limit the amount you're flushing at any given time. And if liberal toilet paper use has led to a clog, your plunger should be able to dislodge the obstruction in short order and restore your throne to full working order. 

More often than not, toilet clogs are caused by items that are not meant to be flushed. (Shocking, isn't it?) Unfortunately, people tend to treat toilets like trash cans, perhaps under the assumption that these magical chairs are practically indestructible. But if they were, then clogs wouldn't happen, would they? It's not just extra wads of toilet paper or the long-lasting Clorox Wipes that can cause severe plumbing blockages, either. Various plastics, feminine hygiene products, dental floss, hair, bacon drippings, and even contact lenses can all cause serious damage when flushed. 

Even wipes that are marketed as "flushable" don't always dissolve once their sewage-bound journey gets underway in your toilet. In fact, multiple companies producing these wipes (including Dude Wipes), have faced class action lawsuits because their products have allegedly clogged up public sewage systems. Professional plumbers generally warn against discarding these wipes in the toilet. To prevent these wipes from ending up where they shouldn't belong, the federal government is working on the so-called "Do Not Flush" legislation, which requires any manufacturer of disinfecting or cleaning wipe products to label whether they are septic-safe and flushable. If you're unsure of what's suitable and safe to send down the chute, it's best to err on the side of caution and follow the Rule of the Three Ps, which says only to flush pee, poop, and toilet paper. 

If the region where you live has hard water, limescale deposits in your toilet's pipes and jets can affect its ability to flush. Hard water contains a large quantity of dissolved minerals, namely calcium and magnesium. The hardness of water differs across the nation, with areas in the Southwest, Midwest, and the Rockies having the highest concentrations of calcium and magnesium. These minerals can accumulate along the walls of the toilet's pipes and jets over time, with every flush contributing a small amount to the buildup. After decades of use, this buildup can be substantial enough to impede water flow, and this may be why your toilet is clogged. Hard water also slows the dissolution of toilet paper once it's been flushed. 

Apart from knowing that your tap water is hard and observing poor flushing performance despite the lack of a visible obstruction, there are a few other clues that mineral deposits are to blame for the clogged toilet. Typically, these deposits will leave reddish-brown stains inside the toilet bowl (these make for an embarrassing eyesore, too). Clean the toilet bowl with a descaling solution on a regular basis to keep limescale from forming in the toilet. 

If you're seeing all the red flags associated with limescale buildup and your toilet is refusing to flush properly, try pouring a mixture of vinegar and water — or vinegar and borax, if you have it — into the bowl. Then scrub the deposits with a toilet brush, reaching as deep into the bowl as you can. If this method alone doesn't help, the hard water buildup could be too deep in the plumbing for you to reach, and the best course of action is to call a plumber to flush the system.