What Is a P-Trap & Why Do You Need One?

Your plumbing system is more than just a bunch of pipes. Though most homeowners and property owners pay little attention to the details, there is a lot of intricate work involved in the plumbing. For instance, the p-trap is a component that many households take for granted. In reality, this unremarkable looking part of your plumbing plays a very important role in flushing things away, keeping your home smelling fresh, and preventing deep clogs. In this article brought to you by the folks at Neighborhood Plumbing, we will go over the functions and types of p-traps. You are always welcome to call Neighborhood Plumbing if you need service or repair for your plumbing system.

What Is The P-Trap?

Take a look under any of your sinks in the bathroom or kitchen. You will notice that the pipe leading from the basin of the sink forms a u-shaped dip. This dip is also found in the s-trap, but an s-trap dips twice while the p-trap only has one dip before straightening horizontally again. This p-trap looks like the letter P rotated 90 degrees clockwise.

What Does the P-Trap Do?

The p-trap does not do anything in the active sense. It does not move but it does have an impact on how the plumbing system works. In fact, it has quite a few benefits.
The dip we mentioned earlier is filled with water at an even level, meaning air cannot get past. This acts as a filter preventing air and extreme odors from entering your living or working space. A dry p-trap, though, will allow these foul odors to rise into your building. This dry p-trap is therefore an early sign of other plumbing issues.
In addition to providing a line of defense against sewer gases, the p-trap helps with flushing and draining. It also helps prevent clogs from forming deeper in the plumbing system by trapping debris in the u-shaped dip. Unclogging this portion is much easier than getting in the walls.

Types of P-Traps

We have already mentioned that there are s-traps and p-traps. Many people confuse the two, but s-traps have two dips, giving them the s shape. Both were designed to do the same thing, which is to provide a barrier between your home and the sewer. However, p-traps came later as a response to the main issue with s-traps, which is that they tend to siphon away too much water and leave the drain dry.
Though an s-trap is not a type of p-trap, there are a couple of options when you choose a p-trap. You basically have two choices when it comes to the p-trap: metal or PVC. Metal p-traps are great if you use hot water consistently and for prolonged periods. This is because metal p-traps are heat resistant. However, they corrode and must be replaced every five to ten years. PVC has a far longer life span but are not found in large buildings because they do not offer the durability of metal p-traps.