No, based on expert recommendation, installing two (2) P Traps under a kitchen sink is not ideal. this is because It can lead to inadequate drainage, and when there is inadequate drainage, there wil be an increased chances of clogs, and potential leaks.
The International Residential Code (IRC) states that only one trap is allowed between a plumbing fixture and a trap arm. This is because having 2 P-Traps can create a siphoning effect that can pull water out of the Traps and allow sewer gases to enter the home.
we should understand that P-Trap has one main function, which is to use it’s water seal that was created to stop unwanted gases from escaping or flowing into our houses;
Again a P-Trap in the sink also serves other purpose in some cases, they stop food particles and debris from going down the drain . And by installing two P-Trap can compromise the effectiveness of the P-Trap .
Hence having two P-Traps would be redundant and can cause various issues. First you might find yourself dealing with a P Trap that has issues with inadequate drainage, increased chances of clogs, and potential leaks.
Additionally, this practice of installing multiple Traps on one just sink is against local plumbing codes.
If you’re experiencing a problem with your sink’s drainage or considering modifications, it’s best to consult a licensed plumber who can provide expert advice and ensure that the plumbing system is installed correctly and in compliance with local regulations.
Cases where Two P-traps Can Be Installed
Although we have rightly pointed out that installing two P Traps in one sink is not recommended but there are instances where you have to put certain things into consideration.
what about if your kitchen sink also has a food waste disposer? and we all know what problems comes with that. First a kitchen sink with a food waste disposer is known to produce lots of grease and debris and all this can clog the sink quickly.
So in this case, you might decide to install a special kind of P Traps for that food waste disposal in addition to the normal P-Traps , this is to reduce the risk of a clog in one of the traps
But other than that, just make do with one P Trap on your kitchen sink.
What we have said so far whether you can install Two P-Traps
what we have said so far is that, the only time you might consider installing two P Traps is only when your Kitchen Sink has a food waste disposal.
Here are some of the reasons why it is not recommended to have 2 P traps under a kitchen sink:
- It can be more difficult to clean the drains.
- It can increase the risk of a clog.
- It can be more expensive to install
What happens if you have 2 P traps?
If you have two P-traps installed in a plumbing system, it can lead to several issues and complications.
let’s take a look at the challenges of installing two P Traps on one sink below :
Multiple P-traps can restrict the flow of water through the pipes, causing slow drainage or complete blockages. The extra P-trap creates additional bends and obstacles that hinder the smooth passage of wastewater.
Installing two P-traps will make water dry out or evaporate from the P Trap quickly and when there is a loss of water, foul odours, gases will be released to your living space as there won’t be a seal to stop the flow.
Having two P-traps increases maintenance cost. since having two P traps means there are more components of your P Trap to maintain and clean. If one of the P-traps becomes clogged or develops a leak, it becomes more challenging to access and resolve the issue.
having Two P Traps under a kitchen sink is against Plumbing codes and regulations. It is always good to adhere strictly to these codes especially when dealing with P Traps.
The codes are there to guide and also help minimise the risk of leaks and when this codes are not adhered to then you are likely to face legal issues, also face issues of not able to sell or rent your house since its violate local codes.
If you rent or buy a new property and you discover that there are two P Traps in one sink, do your best to consult a professional plumber to help come in and access the situation as he will be in the best position to inspect, find out the reason why the Two P Traps were installed in the first place and give best course of action take take..
Do I need 2 P traps for a double sink?
No, having double sink doesn’t warrant two P-traps. It is against international residential plumbing code. what we mean here is that there is no need for two P-traps on a double sink.
All you just need to do is to connect your double sink to a single P-trap.
Can a double sink have one drain?
yes this is the best practice everywhere. A double sink should have or make use of just one drain.
The centerlines of the outlet (tailpiece) of both sinks must be no more than 30 inches horizontally from the trap centerline, according to the International Residential Code (IRC)
by having one P Traps for a double sink drain will ensure that a steady water flows is maintained and thus help the drain efficiently drain properly, making it not to clog more often. Additionally, have just one P Trap help reduce maintenance cost.
Why does one side of double sink not drain?
the pipes are prone to blockage from anything from debris, food particles, grease, and untill this problem is address you might be experiencing same issue.
The P Trap can be clogged with debris and hence there won’t be free flow of water.
vent pips aid free flow of water but if blocked or obstructed, it can affect the free flow of water.
An incorrectly installed P Traps can result to sink not draining, so ensure that the plumbing connections is not faulty.