‘Should I Call a Plumber?’ How to Diagnose—and Fix—a Plumbing Clog

When to do it yourself and when to call a plumber

Put down the phone and grab your handy plunger. zakharovs/Shutterstock

The Romans are often credited with inventing plumbing, but it was the Minoans, Mesopotamians, and Indus Valley civilizations who, about 4,000 years ago, engineered the world’s first sewer systems, complete with flushing toilets. In 1652, Boston was the first U.S. city with a water system; it used hollowed-out tree trunks. In 1804, Philadelphia introduced cast iron pipes. Alexander Cummings was awarded the first patent for a flush toilet in 1775. In the 1920s, tank-style toilets that used five to seven gallons per flush became popular, later improved by water-saving three-gallon versions in 1974.

While plumbing has advanced significantly, all these systems have one thing in common—they can clog.

A clogged drain may seem like a serious plumbing issue, but put down the phone; you might be able to fix it yourself.

Toilet Clogs

The reason you see a plunger next to many home and office toilets is to be ready in case they get clogged. If it’s a new clog, there’s a good chance someone put something in there they shouldn’t have, and a good hearty plunge should dislodge it to get things working again.

If you have a cup plunger—which also works well for sinks, showers, and most other drains—simply place the plunger straight over the opening, making sure it’s at least half covered in water. If it isn’t, add more water, as the plunger is using the air bubble inside it—not water—to loosen the clog. Work the plunger up and down a few times, quickly and forcefully, then pull upward to break the seal. Repeat if necessary. The same technique works for a flange plunger.

If you’re using an accordion plunger, make sure it’s fully covered with water. Like the cup plunger, it uses air, not water, to loosen the clog. Start with a gentle plunge and work your way up to harder ones; otherwise, you might force air around the seal and spray water all over the bathroom.

If the blockage isn’t loosened or dislodged, it’s time to check the main sewer line, check the roof vent, or call a plumber, depending on your skill level.

Sink Blockages

Kitchen sinks can drain slowly or stop completely if food and grease build up over time; bathroom sinks are notorious for clogs caused by soap, grooming products, and hair. Before you break out the handy cup plunger and get to work, remove any drain plugs. In the case of bathroom sinks, you may find it coated with soapy hair; removing this mess with your fingers or the plastic tool sold at most hardware stores may be all that’s needed.

But if it still drains slowly, plug the overflow vent (the little hole you’ve always wondered about at the top edge of the sink). You can use a washcloth, but a strong tape is usually best to seal the system for maximum pressure and to prevent water from spraying out of the hole when you use the plunger. Note that this should be a separate cup plunger from the one you use in your toilet, for sanitary reasons.

If simple plunging doesn’t work, consider buying a plumber’s snake. These metal flexible cables “snake” down the drain and into the pipes to open them up. Home units run from 3 to 25 feet in length. Be careful as you use it, especially with older pipes that could be damaged, making the problem worse and then requiring a plumber.

You might be tempted to reach for a chemical drain cleaner like Drano, but while it will dissolve tough blockages, it can also corrode metal pipes, dissolve PVC, and hurt porcelain. Save the chemical option for emergencies or when the alternative is calling a plumber; use a plunger the rest of the time.

Sink Trap

Drain traps or P-traps can easily become blocked by the debris of everyday life. Happily, it’s an easy fix. All you need are Channellock pliers and a bucket. Unscrew the slip joints on both sides of the trap (the U-shaped part) and clean it out.

While it’s out, you may want to insert your drain snake directly into the wall pipe for a more thorough cleaning. Once done, reassemble the trap and check for leaks before removing your bucket.

Shower or Tub

If you notice that your shower or tub is backing up, clean out the shower drain of hair and debris, using fingers or the tool mentioned above for sinks. Next, use a cup plunger, and if needed, a snake. To lessen future problems, install a shower drain hair guard. If your shower and toilet are clogged at the same time, the problem is most likely your main sewer line.

The Sewer Main

There are three options for blocked sewer lines. The first is using a chemical drain cleaner poured into the shower or tub closest to where your sewer line exits the house. This is the easiest, but again, can damage the pipes and should not be used often. The other alternatives are hydraulic or mechanical drain cleaning; unless you’ve got some really advanced DIY skills, these methods are best left to a plumber.

The Vent Stack

A clogged toilet vent stack, designed to allow sewer gasses to escape, can result in a bubbling, gurgling, malfunctioning toilet. If you’re comfortable moving around the roof, head up there with a garden hose and pour water down the stack to wash away the clog. If not, this is another job for a plumber.

SIDEBAR: Drain Don’ts

Prevention is the best fix. Keep your plumbing system happy by keeping these items out of your pipes.

Calcium Buildup

Never put eggshells down the drain, even if you have a garbage disposal. Their porous nature allows them to bind with fats, oils, and other food waste to ultimately create large blockages.

No Java

Coffee grounds are a great deodorizer in many situations, but not the kitchen sink. They’re hard on pipes, and over time, they build up and form clogs. They can also trap other organic material, leading to unpleasant odors.

Health and Beauty

Even biodegradable products can strain your drain. Don’t flush baby wipes, facial tissues, dental floss, hair, cotton balls, or toilet bowl scrub pads. Don’t flush expired medicine, as it can contaminate water supplies.