By Matt Menke

Matt Menke lives in College Park and is a licensed Maryland home inspector.

What’s something that we take for granted when it works perfectly — but cringe in agony when it doesn’t? It’s a good bet you said “toilet!” So many things can go wrong with our porcelain friends. The issues are mostly out of sight, though, and if there’s even a hint of a problem, many of us just cross our fingers and hope that it will go away. But let’s take the guesswork out of it and look at the five most common things that can go wrong with your toilet.

Unsavory leaks 

A home inspector checks a toilet to see if it is securely bolted to the floor and is caulked around the base. If the bowl rocks or twists with even gentle pressure, it’s likely that either the seal between it and the pipe has failed or the base is not securely caulked. It may not leak sewage (unless there’s also a downstream clog), but it’s likely puffing a little sewer gas into the room with each flush. Leaks can be tiny and hard to spot, but if there’s visual access to pipes below, say in a basement, you can look for stains or wet areas in the subfloor. (Linoleum and vinyl plank around the toilet are waterproof and hide such leaks until mold begins to creep up between the tiles.) A plumber can replace that toilet seal — and it’s better to deal with it sooner rather than later.

Irritating clogs

If you live with children, you’re sure to be familiar with this one. One day, out of the blue, your toilet starts flushing poorly — or even not at all. Most clogs form in the toilet trap, a loop inside the porcelain bowl that is the tightest part of your sewage’s path. So-called soft clogs are large wads of toilet paper that lodge in tight spots, and Drano won’t work on these clogs; only an auger will break them up. Other things that ought not have been flushed, like pencils or plastic toys, will evade the auger, as will a whole lot of other things that aren’t flushable. If your toilet is possessed in such a way, it’ll need replacement.

Wasteful cost

When a tank flapper wears out, it allows water to leak through even when you’re not flushing. An inspector might not spend enough time in your bathroom to notice the tank refilling every few minutes. A plumber can put dye in the tank and see if it appears down in the bowl. Even living there, you may not hear the water running in a spare bathroom or basement toilet. A single sagging flapper can go from letting $0 of water through to $1,000 in a single billing cycle. WSSC customers can seek forgiveness for such incidents once every three years, providing the bill is higher than a set amount — but it’s best not to ever play that card if you don’t have to. 

Then there’s those vintage toilets — popular in old neighborhoods like ours here in College Park— that use 2 to 3 gallons of water per flush. Starting in 1994, new toilets were capped at 1.6 gallons. Unfortunately, toilet design didn’t keep up with the lower flow for decades, And we had to flush them more than once and ended up sending all those water savings down the drain. Toilets are now down to 1.28 gallons, and they work great. Deciding to replace your old water-waster can be a tough call, though; the carbon footprint of getting a new piece of porcelain from China may outweigh some of the savings in water usage. 

Occasional catastrophes

An inspector worth his or her salt will look over each toilet for cracks, which typically are around the floor mounting bolts, which may have been rendered useless by overtightening. And cracks can develop around the trap and result in sewage weeping, in or out of sight. But a cracked water tank can be catastrophic: A full break would spill the tank and open the fill valve to flood your home. Porcelain is strong under compression — it holds up when we sit on it — but it’s weak under shear forces, like a kid leaning against the tank or standing on the rim. The toilet needs to be safe and solidly mounted to the floor in case of kids or someone needing to lean on it for balance.

Other stuff

An inspector should also check how robust the flush is; he or she may notice air bubbling up at the start of the flush or the bowl sucking air at the end. It’s not uncommon for the vent from your plumbing system to be clogged (or maybe there’s no vent at all); a bird’s nest or other debris inside the pipe can block airflow in the vent and be difficult to clear. The vent is a continuation of the waste pipe that extends up through your roof, allowing your flush to displace a puff of sewer gas to the outside. Vents are required by code for baths and kitchens but aren’t always installed. 

The hardware inside the tank may be adjusted badly or could outright fail. A too-short flapper chain shortchanges your flush of water, or that old fill valve can plug up with rust or debris that came in with your water. (Sometimes you can hear the valves take on a  whine or whistle). And if you use chlorine tablets to keep toilet odors down, you’re also shortening the life of all the rubber seals that hold water inside the tank. Leaks at the seals can be sneaky; they can show up as clear water dripping down the supply line or back of the toilet bowl, right onto and even into your floor or wall.

Uninvited water is never a welcomed guest in your home. Good news, though: You, yourself, are now in the best position to notice small changes and become a capable inspector of your own toilet. But if water is not leaving as gracefully as it arrived, you may need help. Just remember to wash your hands before you email me at