Do Showers Need P-Traps? (2 Key Reasons Explained!)

Have you ever taken a shower and asked yourself where the shower water drains before reaching the septic tank or sewer line? All shower wastewater first drains to a u-shaped tubing called a p-trap. But do showers need P-traps?

Showers generally need p-traps because it creates an airtight seal that prevents harmful sewer gasses from going back to your shower space or living room. Additionally, it holds debris and small solids from clogging your shower drain.      

So, though a p-trap may be a small fixture, its role is so fundamental that it’s hard to overlook it.

This guide will look at why shower p-traps are essential and why you should ensure it’s always there. But first, let’s talk more about it, its anatomy, and how it works.        

do showers need P-traps

Where Is the P-Trap in A Shower Drain?

A p-trap is a small u-shaped fixture within the waste drain that connects the shower’s drain with the septic tank or the municipal sewer.  

It usually traps debris and other solids that go down the drain, and as a result, it prevents them from clogging the plumbing system. 

P-traps also stop harmful sewer gasses from going back to your home. They do so by creating an airtight seal around the shower drain.

Here are the parts that make up the anatomy of the shower p-trap:


The inlet is where your shower water drains to before running down the sewer or septic line.

Downward Bend

This part takes a u-shape or p-shape, and it’s usually the part where wastewater flows before reaching the sewer line. 

It usually holds a certain amount of water, and while doing so, it creates a barrier that prevents waste gasses from finding their way back to your bathroom or living space.  


The outlet is the hindmost part of the p-trap that allows wastewater to drain into the sewer while holding larger particles.

Where is the P-trap in a shower drain

Now, Do Showers Need P-Traps?

Generally, showers need p-traps because of these two reasons:

Reason 1: Showers P-Traps Prevent Harmful Sewer Gases from Flowing Back

Imagine living in a house that smells like sewage or rotten eggs? I even don’t think it’s imaginable! Right? 

One significant benefit of installing a p-trap in your shower drain is to prevent the harmful sewer smell from spreading into your home.

Remember that these filthy smells can also pose a health risk. Common sewer gasses to stay away from include ammonia, hydrogen sulfide, methane, sulfur dioxide.

Overall, exposure to the above gasses may cause nausea, pneumonia, headache, bronchitis, fatigue, to name a few. 

Are you still wondering how p-traps eliminate the bad smell?

Well, the downward bent (the curved part) of a p-trap creates a seal that prevents foul sewer smell from spreading to your home. 

So, by any chance you open a p-trap under your shower or any sink in your home, you should not get worried by finding some meaningful amount of water inside.

Reason 2: Showers P-Traps Trap Debris and Other Solid Materials

Imagine your expensive bracelet or your wedding ring going down the drain. Isn’t that frustrating? However, the good news is that a p-trap will help you retrieve it. 

Don’t worry about your p-trap getting clogged by debris as the downward bent ensures that doesn’t happen, thus quickly preventing your shower drain from clogging.

Note, however, that p-traps must be heavy enough not to be forced down the drain by water pressure. That allows you to retrieve valuables that escape into the shower drain quickly.

What if Showers P-Traps Are Clogged?

Sometimes, too much clogging by dirt, gunk, and calcium render the p-trap less effective. In such a case, water drains slowly into the opening of the shower’s floor.

That, however, doesn’t mean that you don’t need it. What you should do is clean the p-trap.

Overall, you can opt to remove the p-trap and clean it or clean it without removing it. Let’s look at both options.

Option 1 – Cleaning by Removing the P-Trap

You can follow the steps below to remove and clean the p-trap:

  • Locate the p-trap on your shower floor. It’s usually close to the drain area
  • Remove the tiles above the p trap
  • Once you find it, position a bucket underneath it to avoid water spills
  • Disconnect it (p-trap) from the outlet pipe
  • Soak it in a solution of baking soda and white vinegar for about 15 minutes
  • Use a brush to clean it and rinse it using clean water
  • Once the p-trap is clean, connect it back to the outlet pipe and fit it correctly as it was

Option 2 – Cleaning Without Removing P-Trap 

When it comes to cleaning the p-trap as it is, you can use any of these approaches:

a) Snake Auger

You can make your snake auger or get one online such as the  Plumbing Snake Auger. Not only will it unclog your p-trap, but you can also use it to unclog almost all your home drains.

The good thing about snake augers is that they are flexible to reach the curves of the p-trap, thus effective in dislodging the dirt and gunk buildup.

It’s essential, however, to wear protective gear when using snake augers to avoid injuries.

Where Is the P-Trap in A Shower Drain
b) Baking Soda and Vinegar Direct Pour

You can also pour vinegar and baking soda directly into the p-trap without removing it.

Here’s how to go about it:

  • Use ½ cup baking soda and mix it with a cup of white vinegar
  • Pour the mixture into the shower drain slowly and cover the drain for 15 minutes
  • Pour plain water in the drain, and hopefully, the mixture will have softened the clog
c) Enzyme-Based Drain Cleaner

While most chemical cleaners effectively clean the p-trap and shower in general, they can be too strong for plumbing work. So, if you are looking not to damage your pipes, use an enzyme-based cleaner.

They usually act slowly but ensure they eat all the clog without damaging your pipes. 

If you are looking for a more natural drain cleaner, you can buy the Biokleen Bac-Out Natural Bathroom Cleaner

This enzyme-based drain cleaner not only cleans your shower drain from soap scum, unpleasant smell but also deodorizes it making your shower smell fresh.

What if Shower P-Traps Are Worn Out?

In case of an old p-trap, you should replace it. P-traps will naturally wear out as they are exposed to too much dirt and gunk. So, you must monitor them periodically to ensure you replace them when they become too old and ineffective.

Given that shower p-traps fit under the shower drain, which is not easily accessible, replacing a shower p-trap is not as easy as replacing a sink p-trap.

For this reason, you should replace your shower p-trap when renovating the bathroom flooring.

Here’s how to go about it:

Using an electric saw, cut the floor around the shower drain by about 12 square inches to create enough working space.Remove the square flooring you cut and unscrew the piping between the outward bend and the drainpipe before pulling out the flooring.

Apply plumbing glue to the inside of the new p-trap and connect it to the outlet piping. Ensure they stick firmly together. When done, reattach the floor piece you had cut earlier and place the shower drain into position, and that’s it.

If you decide to replace a p-trap in your shower drain, one top recommendation is the EasyDrain Ref. 510 Expandable P-Trap. This p-trap is flexible, and you can remove it easily for unclogging when cleaning it.

do showers need P-traps

Shower P-Trap Alternative

Remember, a p-trap is necessary for preventing sewer odor and clogging in your shower line. That, however, doesn’t mean that it’s the only fixture that can do the job. Its advantage over others is that it’s more efficient and cost-effective.

However, in case you forget to install a p-trap, you can opt for any of these two alternatives:

Remember, if a shower drain lacks a p-trap, it may cause damage to the shower line, and sewer odor may penetrate your home.

One fantastic alternative to showers p-traps is an HepVo Valve.

This waterless valve seals the foul air from getting into your home. It is also ideal for more tight spots like under the shower drain. 

An HepVo Valve is smaller than the p-trap but like a p-trap. It doesn’t damage your plumbing system.

People Also Ask

1. Where Is the P-Trap in A Shower Drain?

You can find the p-trap under the midpoint of the shower or adjacent to the shower drain. Note that if you install a p-trap far from the drain, the filthy sewer smell will draw back into your home.

Remember, if the distance from the gutter and the p-trap is long, the more stinky your bathroom will be.

2. Should Showers Have P Traps?

For the sake of preventing the backflow of odorous sewer gases, shower drains should have p-traps. Besides, a p-trap also holds debris and gunk, protecting your drain from clogging.

3. How Far Can P-Trap Be from Shower Drain?

A p-trap needs to be not more than 5 feet from the shower drain. However, the closer the shower drain is to the p-trap, the better results. If p-traps are far from the shower drain, the chances are that the awful sewer smell will enter your home.

4. Does P-Trap Have to Be Directly Below Shower Drain?

It is not a must for a p-trap to be directly below a shower drain. However, it should be as close to the drain as possible. The closer the p-trap is to the drain, the easier it will prevent bad smells from going back to your home. Moreover, it’ll make cleaning easier.  

Do Showers Need P-Traps? Closing Thought:

Though a p-trap could be an extra cost or extra work, installing it is essential. As discussed, you need it to prevent odorous sewer smell from getting into your bathroom space and preventing drain clogging.

So, check your shower’s p-trap today and replace it if it’s worn out. Remember also to fit this essential shower fixture when building your shower. But if you cannot do it, find an expert plumber to hire.

Also Read: