Can One Clogged Toilet Affect Another?(Solved)

Can One Clogged Toilet Affect Another?

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Can One Clogged Toilet Affect Another?

A clogged toilet is an unpleasant event in many people’s houses and is one of the more common plumbing problems a homeowner will encounter.

There are many causes for this issue, which range from blocked toilets to overflowing pipes. Regardless of the problem, you can fix clogged toilets without extensive damage to your home or expensive repairs.

Yes! A clogged toilet can affect another toilet if it’s connected to the same drain line. Often, you will find pipes in pairs, one for each toilet. So, when clogging occurs, it restricts water flow between the pipes, which equalizes pressure and balance the flow. This pressure difference creates a siphon effect, potentially affecting the entire system.

However, the reality is that, generally, clogging resolves itself and alleviates the pressure, but it depends on the source of the clogging.

For example, a siphon effect is not likely if there is a clog at the end of the line, like in your main drain pipe.

A blocked toilet will likely affect another if both toilets share a common drain pipe. Also, when one toilet becomes clogged, it can push water into the U-tube, causing seepage through both toilet bowls.

This is because an overflow pipe does not separate the U-tubes pipe ways.

A capped-off overflow pipe may have set up a siphon effect unknowingly. If you have a capped toilet, remove the cap or blockage if this happens to you.

The siphon effect will break and will not happen again.

Can One Clogged Toilet Affect Another?

You should pay close attention to the clogs in your home because one toilet clog can affect another if you connect it to the same drain line.

This can either be through a toilet with an overflow drain pipe or a two-toilet sink with a separate shower or bathtub.

What To Do When Both Toilets Are Clogged?

What To DoExplanation
Avoid Flushing The Toilets-It can overflow and flood the toilet.
-It can interrupt the sewage system.

-If you don’t have time to let them unclog, use the plunger that is in your kitchen.
Locate The Blockage-Use a plumbing snake or a floor jack and unclog the pipe.
-Check the visible portions of the pipe to see if there is debris and try to remove it.

-Use a plunger to push the debris back to the main pipe.
-Call a plumber to unclog the toilet.
Plunge The Toilet-Take the plunger and plunge it into the bowl of the toilet.
– If you have a two-piece bathroom, plunge it on both sides.
-If the blockage is still there, plunge it for a few minutes before trying something else.
Call A Plumber-Call a plumber; they will unclog the toilet.
-The plumber can have your toilets clogged in one day or less.

 -They will give you tips on what to do if you clog the toilets and how to prevent it from happening again.

Will A Clogged Toilet Eventually Fix Itself?

It depends on the type of clog, This may include:

Water Soluble Clogs

When a clog is made of water-soluble materials, your toilet will eventually begin to function normally again as the material dissolves and washes away.

These clogs boast a composition of hair, soap, paper towels, and other disposable items.

Sometimes, the clog breaks up on its own. Other times, you may have to break it up with a plunger manually.

However, the best way to remove a clog is by flushing it away with plenty of water. Make sure you flush the clog down the drain to ensure its removal.

Oil Soluble Clogs

Some clogs are made of oil, which can lead to prolonged clog problems. These clogs include hair and debris built over time; you cannot flush them with water alone.

Try a different plunger method to break up the clog.

Boiling water dissolves many of these clogs, so if flushing doesn’t work, try boiling some water in the toilet bowl to see if this helps.

Also, you can use a chemical degreaser or drain cleaner to break up the clog.

These chemicals are potent; you should only use them as a last resort if the toilet clog is still not breaking up after running boiling water and plunging the toilet.

How Much Does It Cost to Unclog A Main Sewer Line?

An average rate for an experienced plumber to do a standard sewer cleanout is $150-$200 for a typical 2-man job.

The cost may range from $300 to $800 or more for major repairs or replacement of aging pipes full of roots, tree limbs, and other debris.

The cost of replacing a main sewer line can be $6000-$10,000. Other pipe replacements can run as much as $5000-$20,000.

There are several other factors to consider, including the size and location of your home or business.

Generally, if the blockage is in a basement, replacing smaller diameter roots around the house and catch basin is more cost-effective than just digging up the entire yard for a cleanout.

Your local sewer line can be clogged anywhere from the main trap to the pipe that connects to your home or business.

Trap$175 to $475
Waste Pipe$109 to $214
Vent Stack$101 – $176
Main Sewer line$350 -$650

What Causes Clogged Toilets?

There are many causes of clogged toilets:

Too Much Toilet PaperToilet paper accumulation with little water to work with will cause a clog.
Grease And Oil-Causes water soluble clogging.
-Removable by using a chemical such as sodium hydroxide to dissolve it.
Foreign Objects-Toys, cotton, and sanitary napkins are all common foreign objects found in toilets.
Debris-Dirt, sand, and leaves cause clogging in the toilet.
Hair-Hair is left in the toilet bowl and will clog the pipes.
Pet Waste-Pet waste, such as a dog or cat waste, will cause a clog.
Flushable Items-Flushable items such as baby wipes, feminine products, and medicines will clog the pipes.
Blockage From Another Toilet-When flushing, the water from the toilet will cause blockage in the pipes, which is why toilet paper is recommended over other items.

How to Cleanse Two Clogged Toilets at Once?

There are various techniques to unclog a toilet:

1. Use A Plunger

Using a plunger is easy. Place the plunger over the water in the toilet, form a seal around the base, and plunge. This should remove any blockages that are in the bowl.

2. Use A Plumbing Snake

Insert the snake into the drain and let it go around the pipe. This will help to loosen any clogs in the toilet pipes.

3. Use A Chemical Cleaner

You can find various chemical cleaners in most stores’ plumbing sections, such as Drano. Pour some of the cleaners into the toilet and let them sit for a while.

Afterward, flush the toilet to push out anything loose with these chemicals.

3. Use Boiling Water

Many people use this technique since it works most of the time. So, pour boiling water down the drain until you see it drain away, or use a kettle or pot full of boiling water to pour it down the drain.

Can One Clogged Toilet Affect Another?

This should let lose any clogs in your toilet pipes and drain.

4. Use an Auger To Snake Through The Drain

An auger is a section of metal wire that boasts coiling around a spring-like mechanism to allow it to pull back into place after use. Use the auger to snake through the drain.

You can do this by putting the spring mechanism off to one side of the tank, rotating it so that the lower end is on top, and then driving it down into the drain.

This will help to loosen any clogs in your toilet pipes and drain.

5. Call A Plumber

If none of the above techniques work, call a plumber to help you unclog both toilets.

Why Are Both My Toilets Backing Up?

1. Drain Line Blockage

Drain line blockage means the toilet can’t flush properly because the water has nowhere to go.

Common causes of drain line blockages are tree roots from a storm or sludge buildup in pipes. Such can cause your toilets to back up.

2. Low Water Pressure

Water may not reach the toilet bowl fast enough if your toilets boast low pressure. This is especially true for toilets with a low water level in the bowl.

As such, flushing will be ineffective, resulting in your toilet backing up into a dirty mess.

3. Broken Flush Valve

If you break the flush valve, water can’t drain properly in the tank, and it overflows, causing your toilet to back up. A sign of a broken flush valve is a leaking tank or a flapper that won’t stay shut.

4. Blocked Overflow Pipe

If the pipe from the tank to the bowl is blocked by debris, such as kinks, it can’t drain water from the tank properly. This creates a backup in your toilet bowl, which forces water to overflow onto your floor.

5. Leaky Toilet

If your toilet leaks, water will seep into the floor or basement and cause a backup in your toilet bowl. This can also result in mold growing on your floor.

6. Old Toilets

If you have old toilets with a worn-out seal, this can cause the water to drain slower, forcing the water to back up in your toilet bowl and overflow on your floor.

Why Did One Toilet Regularly Clog, And Now Another One?

1. Sewer Line Blockage

Sewer line blockage was the cause of the first toilet clog. The buildup of waste and other gunk may have created a stoppage in the system and caused one or more pipes to back into a toilet.

2. Debris Blocking the Flapper

Debris such as paper towels, old rags, or crumbs caught in one or more pipes may have caused the second blocked toilet – This is where a flapper clogs, which would prevent water from flowing properly through these areas.

3. Flapper Stuck in The Closed Position

If your plunger does not work, the flapper may be stuck in the closed position. In this case, toothpaste, soap, or other debris could have held the flapper.

You will have to clean out the debris from the toilet’s plumbing system.

Ultimately, this will require closing off the toilet and removing its interior components to get at that debris, which could also be causing a clog somewhere else.

4. Low Water Pressure

If the water pressure is very low in the first instance, a toilet is less likely to flush effectively.

Water pressure, or lack thereof, could also contribute to the second case since pressure is affected by the amount of water flow. A faulty water meter may cause this.

5. Toilet Overhaul

You could have altered it in some way that no longer allows it to flush effectively. This could include the installation of new fill valves and tanks that you need to install correctly.

6. Plumbing Problems

A pipe too small for the toilet may cause a clog, a problem that some homeowners run into when installing fiberglass or other types of toilets in places where older models were positioned.

A balloon knot may also cause it, which is unusual since these are not normally found in plumbing pipes unless they have been recently replaced with new installments.

Can Bleach Unclog A Toilet?

Yes! Although it is not the best technique for unclogging your toilet, you could use bleach to unclog the toilet.

Bleach does have some corrosive properties that can help break down clogs, but these properties are only effective in acidic conditions.

Using Bleach to Unclog a Toilet:

  1. Flush the toilet and put 1/8 cup bleach into the bowl. Let it sit for 10 minutes.
  2. Add 2 quarts of warm water to the bowl and flush. If this does not work, repeat steps 1-2 twice more.
  3. Flush the toilet, and allow it to sit for about 20 minutes.
  4. Brush aside any clogged material with a toothbrush.
  5. Check your toilet to see if you have successfully unclogged the toilet.

Although using bleach to unclog your toilet is fast and effective, it can be dangerous if you learn how to use it properly.

The bleach can burn the skin and irritate the eyes. Also, remember that you can use only 1/8 cup at a time since too much will cause the clog to dissolve into the bowl.

Can One Clogged Toilet Affect Another?

Finally, bleach is ineffective in removing hair from the bowl, so you may need to take a few more steps to clean your toilet.

What Chemicals Do Plumbers Use to Unclog Toilets?

Sodium Hydroxide (Caustic Soda)Highly soluble in water, allowing it to easily flow through pipes and reach areas that clogs may block.

Highly alkaline allowing immediate dissolving of grease and fats.
Hydrochloric Acid (Muriatic Acid)Highly soluble in water, allow it to easily mix with water to create an effective cleaning solution for pipes and other plumbing fixtures.

Affordable and relatively inexpensive, making it a cost-effective option for many plumbing applications.
Copper Sulfate and Sodium Hydroxide (Blue Dye and Caustic Soda)Highly soluble and acidic, which allows cleaning action to reach the clog and dissolve the debris causing the blockage.

Non-caustic formula is safe for plastic and most metal plumbing fixtures.
Xylene (Toluene)Extremely effective for dissolving mineral and grease deposits in pipes, tanks, systems, and fixtures due to its ability to dissolve and suspend fats, greases, and waxes.

Ideal for commercial applications where regular disinfectants are unsuitable or do not provide the desired effect.
Potassium PermanganateBoasts solid oxidizing properties that allow it to dissolve and break down grease and mineral deposits in pipes.

Keeps fungus at bay and prevents bacteria from flourishing in tanks, pipes, and systems


Clogged toilets are one of the most common plumbing problems that you can encounter.

The article boasts various ways of unclogging your toilet, and I hope it provides you with the knowledge you need to resolve any clogs.


Hi! I I faced many questions from customers about different products, and there was hardly any help on the internet. After learning all the things about these products as a manager the hard way, I decided to start a blog and help other people.

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