HomeHome OrganizationComparing tow Plumbing Essentials S Trap Vs P Trap

Comparing tow Plumbing Essentials S Trap Vs P Trap

When we talk about ‘traps’ in bathroom plumbing, we mean a special way of setting up pipes to prevent bad smells from entering your bathroom.

The pipe is made to hold a little bit of water, which seals the pipe and stops stinky gases from the sewer from coming back into your bathroom.

We use ‘traps’ to make a water seal that catches these gases. The two common types of traps are the T trap’ and the ‘P trap.’

The main difference between an S trap and a P trap is their appearance. They’re named after the letters S and P because their shapes are similar to those letters.

Both trap types do the same job, but their shapes make them hold water differently. Because of this, the P-trap is better at keeping away the bad gases than the S-trap.

This article will explain the differences between these two types of traps so you can understand why the P trap is better.

Differences Between S Traps vs P Traps: A Quick Overview

Shape Shaped like an “S” or snake shapeShaped like a “P” with a waste arm extension
VentilationLacks proper ventilation, leading to the risk of harmful gases backing upHas a vent that lets fresh air in, balancing pressure and preventing gas backup
Water UsageRequires a larger volume of water for flushing due to siphoning effect and shapeUses less water due to the vent and design; no excess water is pulled down the drain.
Plumbing CodeIt is prohibited in many countries and is being phased out in modern buildings.Commonly used in new buildings, follows plumbing codes for safety
Water RetentionLess water kept in the sinkEffluent held in the trap
SizeRequires larger piping to accommodate water conservation needsUses smaller pipes since it doesn’t need to conserve water, takes up less space
MaintenanceOften requires frequent maintenanceTypically it does not require regular maintenance
Modern PreferenceRarely preferred nowadaysPreferred in modern setups
Water ConservationNeeded in the sinkThere is no need to conserve water in the sink
Draining System OutletPositioned on the floorMounted to wall

In our recent article we discussed Steam Clean Oven vs. Self Clean: Which Is More Effective?

What Is the Function of a Plumbing Trap?

A trap is a helpful part of pipes in sinks, tubs, and toilets, even if it sounds complicated.

A trap system has curvy pipes that stop smelly gases from sewage systems from coming into your building.

Some common gases are:

  • Carbon Monoxide
  • Methane
  • Nitrogen
  • Hydrogen Sulfide

The best thing about plumbing traps is that they keep your family safe and healthy.

Those harmful gases could come into your bathroom or kitchen without a trap.

When you flush your toilet or use your tub or sink, the water stays in the pipes, usually the curves. This trapped water prevents bad gases from entering your kitchen or bathroom.

What is a S trap?

What is a S trap
Source: Structure Tech Home Inspections

An S trap is a type of plumbing fitting used in drainage systems to prevent the backflow of sewer gases into a building or residence. It consists of a curved pipe shaped like the letter “S” or “U.” This trap is typically installed under sinks, basins, and other fixtures in plumbing systems.

You might aslo want to read about Pipe Dope vs. Teflon Tape: Understanding The Key Differences

What is a P trap?

What is a P trap
Source: Home Oomph

A P trap is a vital plumbing component used to block the reverse flow of sewer gases into a residence via the drainage system. You can also encounter P traps in various settings, including waste pipes, wastewater systems, and septic tank lines.

Differences between a bottle trap and a P trap

Differences between a bottle trap and a P trap
Source: Home Guide Corner

There are some key differences between these two plumbing fittings that can assist you in making the correct decision for your home.

Discover More: Decoding 14/2 vs. 12/2 Wires: Choosing the Right Wire Gauge


The primary distinction between a P-trap and a bottle trap is immediately evident: P-traps are not well-suited for compact spaces, while bottle traps are.

Water Flow

Another distinction between a P-trap and a bottle trap is the way water flows through them. P-traps feature external bends, while bottle traps have internal bends.

The positioning of bends inside the pipe for bottle traps results in distinct flow patterns, offering specific plumbing advantages for both P-traps and bottle traps.

P-traps are generally more suitable for large-scale plumbing projects, whereas bottle traps are the preferred option for smaller residential installations.


There is also a difference in cost between P-traps and bottle traps. Bottle traps, being smaller and requiring less material than their larger counterparts, typically come with a lower cost for both manufacturing and installation.


When deciding between a bottle trap and a P trap, it’s crucial to consider ease of cleaning. A bottle trap can be conveniently cleaned by removing the cap and reaching inside, while a P trap necessitates removal for cleaning.

Applicability to Specific Areas

Although bottle traps offer easier installation and maintenance, it’s crucial to be aware that they might not be permitted in certain regions. Therefore, it is essential to research the regulations applicable to your area.

Even if a bottle trap appears to be the ideal choice for your situation, local or building regulations in your area might prohibit its use.

Read More: KitchenAid Dishwashers vs Bosch: Features Comparison

S Trap vs. P Trap: Are They Alike?

S Trap vs. P Trap Are They Alike
Source: Canva

While both of these traps fulfill a similar function in your household, it’s important to note that there are significant distinctions between them that warrant consideration.

An S trap is a more fitting choice for smaller spaces due to its generally smaller size and easier installation. It also tends to be more cost-effective than a P trap. Nevertheless, it’s essential to verify local regulations as S traps may not be permitted in all areas.

Conversely, a P trap is better suited for larger areas, although it can be more challenging to maintain since it requires removal for cleaning. A P trap offers improved water flow and is the preferred option for commercial projects or larger water systems.


If your old toilet is giving you trouble, like leaking, and you want to put in a new one, there are many different toilet options to pick from. When choosing a toilet, you not only have to think about the brand but also decide between two types: S-trap or P-trap toilets. The differences between them are explained earlier.

Remember, no matter which type of toilet you go with, it’s a good idea to have a professional plumber install it. They know much about this and have the experience to do a better job.

Read Next: Nails vs Screws: Choosing the Best Option

Gabriel, is an expert in solving home-related problems, specializing in home appliances and organization, offering insights for optimizing activities and maintaining an orderly living space.


Please enter your comment!
Please enter your name here

Recent posts