Toilet Backing Up Into Shower: What to Do Next

Toilet Backing Up into Shower

Some things should remain separate: forks and outlets, oil and water, and sewage and showers. Unfortunately, toilets backing up into shower drains is all too common. And when these connected systems mix, it can be a harbinger of worse issues to come.

Luckily, if you're dealing with sewage in your shower, there are ways to fix it. In this article, we'll tell you what to do.

What Causes Your Toilet to Back Up into Your Shower?

When you flush your toilet, water flows down through your sewer lines and into the sewer main. If water from your shower drain comes back up during this process, it could disrupt the shower's functionality and hinder its efficiency.

Your sewer line could have become blocked due to several causes; here are a few likely candidates:

Tree roots

Trees need water, and your sewer might be where they get it! When trees become desperate for water, they may penetrate leaky or weak pipes. Even trees from across the street could reach for your sewer line to obtain water. Eventually, these roots could break through and cause blockages or ruptures.

Objects flushed down the toilet

Children's toys, feminine hygiene products, food, paper towels, baby wipes, and even wads of toilet paper can build up and clog your sewer, leading to a backup.


Every time we shower, we lose just a little hair. In general, it's not a big deal and most of it goes down the drain just fine. But over a long enough period, hair can accumulate in your drain to form an obstruction. This blockage prevents fluids from draining as intended and even stops drainage altogether if hair accumulates in drains. This can happen faster if you have very long hair, which catches in the drain more easily, or if you bathe your pets in the shower. In these cases, we recommend installing a mesh hair catcher to your shower drain.

Pipe scale

Pipe scale is a mineral deposit that usually consists of magnesium or calcium deposits and is naturally present in unfiltered water. As these elements flow through your drain, they can attach to the pipe's walls, forming layers that can block your sewer line and lead to backups.


Grease, fat, and oil buildup in drainage systems is an ongoing threat that needs to be managed carefully. They often get washed into sewer lines from dirty dishes and cause blockages that affect every drain in your home.

Other miscellaneous substances

It doesn't always take just one thing to block your sewer lines. Sometimes, multiple factors work in concert against you! Laundry detergent or soap build-up, in particular, may contribute to blockages in both toilet and shower drains.

Imagine that your drains are like rivers with many branches. Smaller pipes merge into one larger pipe, and pipe is partially blocked up, backups could happen at every branch. This includes those connected to showers and toilets.

How to Prevent Your Toilet from Backing Up Into The Shower

Time to fix the problem! Unfortunately, drain cleaner is unlikely to do the trick and could potentially make things worse; try the below strategies instead to clear away clogs in your sewer system.

A good first step is to switch off your main water source before doing anything else. If a substantial shower drain clog causes floodwaters to build up in your bathtub or shower drains, flooding is imminent, as water cannot drain away through these outlets. You will likely find your main shutoff near or in your basement/garage/water heater area.

Use a drain snake

A drain snake can help unclog most drain lines. Start by carefully feeding a toilet serpent into the toilet drain - be careful not to leave permanent marks on your toilet finish! As it enters the drain, spin the snake clockwise and then counterclockwise before pulling out slowly. If the shower drain is the culprit, remove the screws from the drain cover first.

With the cover removed, push the snake down through the curving pipe, spinning clockwise then counterclockwise when pulling the snake out. With any luck, this should clear any obstructions in your drain.

Clear the air

Toilet water may sometimes back up into your shower due to a blocked vent pipe. Locate this pipe by climbing to your roof's attic, most likely above your bathroom. Use a flashlight to search its length using retrieval tools. If the debris is beyond the reach of a retrieval tool, use a garden hose to spray out any obstructions.

Call in the pros

If all else has failed, it's time to contact Mr. Rooter Plumbing for professional assistance. Our experienced team will assess the issue and recommend the right solution, including everything from tree root removal to pipe scaling services.

Toilet Backing Up Into Shower FAQs

How do I clean sewage backup in my shower?

Having a sewage backup in your shower is undoubtedly a distressing situation. Not only is it unhygienic, but it can also pose health risks if not addressed properly. Here's how you can clean up sewage backup in your shower safely and effectively:

1. Assess the situation: Start by identifying the source of the sewage backup and determining its severity.

2. Use proper personal protective equipment: Put on protective gear such as gloves, goggles, and a face mask before attempting any cleanup.

4. Turn off the water supply: Locate the main water valve for your home and turn it off to avoid any complications during the cleanup process.

5. Remove standing water: Use a large bucket or a wet/dry vacuum to remove as much standing water as possible.

6. Dispose of contaminated items: Discard any items that have come into contact with the sewage backup, such as shower curtains, rugs, or towels. They may not be salvageable.

7. Clean the affected area: Prepare a mixture of bleach and water to disinfect the affected surfaces thoroughly. Scrub the shower walls, floor, and drains using a stiff-bristle brush.

8. Rinse and sanitize: After cleaning, rinse the area with clean water and sanitize it with a disinfectant solution. This will help eliminate any remaining bacteria or odors.

9. Unblock the drain: If the backup is caused by a clogged drain, use a plunger or a plumbing snake to clear the obstruction. Alternatively, you may need to contact a professional plumber.

10. Dry the area: Use fans or open windows to promote air circulation and aid in drying the affected area. Moisture can lead to mold growth if not addressed promptly.

11. Monitor for signs of contamination: Keep an eye out for any lingering smells or signs of recurring backups. If you notice any issues, taking further action or seeking professional assistance is crucial.

12. Prevent future backups: Regularly maintain your plumbing system by avoiding flushing inappropriate items down the toilet and scheduling routine drain inspections.

Rely on Mr. Rooter for Professional Help with Plumbing Backups

A toilet overflowing into the bathroom shower is never pleasant. Understanding the cause of this issue can help you take preventative steps against repeat occurrences.

If your toilet has already backed up into your shower, Mr. Rooter is available 24/7 for help. We've got you covered no matter the time or day! Rely on us for toilet installation, sewer line replacements, and more!