Captain Leaky New Member. The S-trap is used when the piping runs underneath the floor because it cannot retain … It's through piping bends and curves that some water remains behind to block odors and sewer gases that can reenter the bathroom. It then loops over and exits downward. When the sink is empty, water flows back into the trap from the pipe and air is sucked back in through the vent, equalizing the pressure to keep the trap full of water. With an S-trap, the drainpipe drops down from the sink and into a conventional trap. Also, a P-trap is probably better if you have a choice-- S-traps can siphon dry even when apparently vented properly (you want some water to remain in the trap at all times to prevent unpleasant--and possibly dangerous-- sewer/septic gas from rising up through the pipes). If you're looking for durability in a P trap that needs replacing, you will find that one made of plastic is generally more durable than a metal one. 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A p-trap can be used weather the drain line comes from the floor or the wall. The only difference between a P-trap and an S-trap is the horizontal length of pipe on the outflow side which allows you to connect the vent. Another potential problem is that when draining, other plumbing units can cause a vacuum that will suck the water out of an S-trap. “metal” walls of this type of p-trap are great for household acids and high temperature liquids. For every 1/4 inch size of yr P-trap counts as a foot from the vent. The 'Bottle' trap takes up less space under a waste outlet and is ideal for pedestal mounted basins where space is usually very limited. S-Trap vs. P-Trap: S-trap vs. P-trap. This will result in an open airway from the sewer lines up through your sink which will allow noxious sewer gases to enter your home. The design of a P-trap will keep the required amount of water is sitting in the trap which act as a barrier to the sewer gases. Considering the bottle trap and the P trap, what advantages does one have over the other, for use in a kitchen? Take the letter P and turn it 90 degrees clockwise. Skew Back Pans >E-mail Removed< Here you go! Traps should be of self-cleansing design with uniform bore and shall not be dependent on internal partitions or other movable parts for retention of water seal. It is used to connect two vertical pipes. Connection of a trap into another trap should not be practiced. S Trap vs P Trap: The Main Purpose of All Drain Traps. P Trap containing water and indicating incoming and outgoing water. This image shows s-trap vs p-trap. This is incorrect. The exception may be a metal P trap made of heavy gauge brass. Various p-traps. ✦ Bottle Trap:Unlike t… Have heard and seen the terms S trap, P trap and J trap used. i would swap out to a full 2'' trap and then just go with a mission band 2'' to 1.5'' tail piece. Personally cant stand bottle traps, flow is dissipated around the bottle and allows gunk to build up, whereas a 'P' or 'S' trap will always be full flow, and provided the sink is kept clean and regular maintenance with boiling water and/or soda crystals is carried out to prevent build up of crud, it'll be rare there's an issue. Looks pretty! Easy Nirman: Comparison between P Trap and S Trap: trap must run horizontally on the outflow side. This image shows s-trap vs p-trap. Have no clear idea of the difference between the three. The issue with S-Traps is 9k n rare occasions when a bunch of water goes down the drain it can pull all the water down the drain emptying the trap which would allow sewer gases to come out from the pipe which is toxic and flammable. Check to make sure that these devices are allowed in your local jurisdiction. The water in a plumbing trap creates a seal to keep out sewer gases. Codes require a p-trap (or an s-trap) any place there is an open drain line that flows into the drain-waste-vent system. A "P" trap,(see image) is the one most used today. Chrome P-Trap: PROS. The 'Bottle' trap, access to clean the trap is by unscrewing the bottom. This will result in an open airway from the sewer lines up through your sink which will allow noxious sewer gases to enter your home. The bottle trap essentially uses a P-trap-style bend … Said it’s actually a p-trap, because the vent is within 5 feet of the weir. A: John Smith, a licensed plumber in Harwich, Mass., responds: Your plumber is correct in his assessment. Q: On a current kitchen remodel, the sink has an S-trap instead of a P-trap, which my plumber says does not meet code. Before discussing the drawbacks to an S-trap, we first need to understand how sink traps operate. The design of a P-trap will keep the required amount of water is … perfectly legal and much easier to snake as the 2'' trap is easier to get around. S-Trap Uses. Understand the S trap is found in most toilets. The problem with an S-trap is that they have the tendency to siphon. If rerouting the drain isn’t feasible, you may be allowed to install an air admittance valve. In a P-trap configuration, the drain also comes down from the sink and into the trap, but instead of looping over and back down, the drain enters a horizontal run before exiting downward. P-Trap Pans. Basiclly, an S-trap is designed to outlet directly through the floor. P-traps are generally considered by most to be more effective and consistent in maintaining water trap compared to S-traps. Re: 1-1/4" vs. 1-1/2" p-trap; Author: Backyard plumber (OK) The arm can be as long as you want it to be. Compact Kitchen Remodel - Common Code Mistakes - Installing an Endless Pool, JLC Online: Best practices for professional builders and remodelers. Hi Team, I called out an ‘s-trap’ and the builders plumber re-looked at it. The problem with an S-trap is that they have the tendency to siphon. good. A P-trap works with a vent to equalize air pressure and allow the trap to remain full of water. A common style is the P-trap, which is highly effective and common. A p-trap is comprised of a tailpiece, the curved trap piece, and a drain elbow. A P-trap toilet’s waste pipe will go through a wall instead of through the floor. Bathroom and kitchen waste traps or u bends remain a mystery to some people but the principle of the trap, be it a P trap, U bend, Gully trap, S trap, bottle trap, pedestal trap, shower or bath trap is exactly the same. A vent allows air to move freely in the system, which in turn allows the trap to maintain that water seal. In other words if your installing a wall-mount sink your plumbing is gonna show, so you would want to go with this type p-trap. starbuild, Nov 8, 2010 #1. However, sometimes, reasons such as lack of space or a typical arrangement of pipes may require one to explore other options. Currently the sink and the washing machine outputs both go through the one 'P' trap (or maybe 'S' Trap, I can't remember and I'd need to dismantle stuff to find out) then along a single pipe out to the gully outside. ✦ S-Trap:The s-trap, as the name suggests, has two oppositely curved sections, which together form an ‘S’. Any expert guidance would be much appreciated. An s-trap is so-called because of its general shape, which looks like an “S”. Occasionally the plumbing under a sink is an “S” trap. But an S-trap loops back down with no way for air to get into the pipe. While the setout of P-trap is the distance from the floor to the centre of the waste outlet on the wall. Even if you have P-traps installed, the water in the trap can dry out over time if the sink is not used. S-traps are now against plumbing code. A P flows better, a bottle uses less space. John Smith is a licensed plumber in Harwich, Mass. When it comes to replacing a P trap in your bathroom or kitchen, making the wrong choice may result in your having to replace the new P trap again, sooner than you would like. A P-trap means the waste outlet through a wall. Expensive! The horizontal run of a P-trap allows water to drain and air to move in the pipe to maintain the trap seal. The set out for an S-trap is the distance from the wall to the centre of the pipe penetrating the floor. The main purpose of any plumbing trap is to be able to create a water barrier. Both work, personally I would fit a P. Re: Is this a legal P-trap? But an S-trap loops back down with no way for air to get into the pipe. A P-Trap toilet in an S-Trap world Hi guys, I once thought all toilets were the same, but now i have a funny smell in the bathroom and I discover the toilet I bought for a makeover a few years ago, and installed by someone else is a P-Trap, and the outlet is meant for an s-trap. A future project I have in mind is to redo the waste piping under our kitchen sink. Have your plumber remove the S-trap and install a P-trap that exits through the back of the cabinet and into the wall. The setout of S-trap is the distance from the wall to the centre of the waste pipe in the floor. The p-trap does this effectively. The waste pipe is always fitted horizontally. Or is it an S-trap? I just to know if the p trap flows better one way or the other? In fact, in some countries, like the United States the S traps are no longer accepted by the plumbing codes and can even be deemed illegal. The following are a few alternatives to p-traps. Like the 'P' trap, the 'S' also requires a fair amount of room around the waste outlet. He can then either tie into an existing vent or run a new vent up through a stud bay and through the roof. There is no "J" trap but a "J" bend,(see image) is the removable part of a "P" trap. Their design makes them less vulnerable to drying out and losing seal: a properly installed P-trap will never lose its water seal. The horizontal run of a P-trap allows water to drain and air to move in the pipe to maintain the trap seal. The P trap in conjunction with the vent ensures that enough water will remain behind to ensure the water plug does its job. InterNACHI® is a registered trade­mark of the Inter­national Association of Certified Home Inspectors rick. This will result in an open airway from the sewer lines up through your sink which will allow noxious sewer gases to enter your home. Likewise, a p-trap resembles a sideways “P”. S-traps may violate code requirements. Why is an S-trap bad, and what’s the best way to retrofit a P-trap? CONS. The typical P trap looks like a P if you envision the flat section of the letter P horizontally. So a 1 inch 1/2 trap can only be 6ft from the vent. Cause there's on 6 1/4 inches in 1 inch 1/2 trap. Again picture a P on its side. I haven’t responded to the client, but the 5 foot rule is a venting rule, and has nothing to do with defining if something is an s or p… that tips free bud. If enough water (say a sinkful) drains through an S-trap, a siphon can be created that sucks water out of the trap, leaving it partially open and unable to seal out sewer gases. S-traps are not allowed because they can create a siphon that leaves that seal partially open. Sarasota FL Home Inspector | Direct Inspections | 941-251-1000, Copyright © 2020 - Direct Inspections - All Rights Reserved, Proudly Serving Sarasota & Manatee Counties. However, like the p-trap, it too requires a lot of space. It is recommended to run all plumbing fixtures at least monthly in order to make sure that there traps remain full of water. Due to this, they cannot efficiently do their job of keeping the sewer gases at bay. A plumbing trap is supposed to stay full of water to seal the pipe and block sewer gases from escaping through the drain. The design of a P-trap will keep the required amount of water is sitting in the trap which act as a barrier to the sewer gases. Diameter of the trap shall in no case be smaller than the diameter of the outlet of the fixture, to which it is connected. problem is the bushing. The trap (and drain) can’t work properly without a properly installed vent in the system (see “Plumbing Vents Explained,” Jun/99). However, P Traps are often preferred over S traps, as S traps have the tendency to easily dry out even when they are well-vented. Setout . The drain elbow for a p-trap fits into the drain pipe which goes directly into the wall. it's a double fixture fitting. 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