We may earn affiliate fees for purchases using our links (at no additional cost to you).
When it comes to plumbing, there are a lot of factors to consider.
What size pipe for the kitchen sink drain is one of them.
Depending on the size of your sink and how much water you use, the size of the pipe will vary.
What Size Pipe For Kitchen Sink Drain?
The standard outlet size for a sink drain today is 1 ½ inches. Yes, that’s it. Sometimes for a double kitchen sink, you may need a 2 inches pipe.
However, sometimes you would also find a 1 1/4 inches tailpiece. Especially, almost half of the older basins are likely to require a 1 ¼ inches tailpiece.
Available Sizes Of Pipe For Kitchen Sink Drain:
Pipe size for a kitchen sink drain:
|Sink System||Pipe Size|
|Older systems||1 ¼ inches|
|Modern systems||1 ½ inches|
|Double kitchen sink||2 inches|
How Does A Sink Drainage Pipe Work?
This is not a complicated system. If you look once, you will get the simplest configuration. The sink drain is at the focal point here.
If you look carefully, you will see that it opens directly to the tailpiece. The tailpiece is a section of pipe set in vertical length.
This tailpiece section then furthers the connection with the P-trap assembly. You will find an extension along with a curved pipe in the P-trap assembly.
So, as you understand, the waste line simply stands at the end of the extension line. The most basic plumbing system consists of these components.
Nevertheless, you will have to invite complications in some cases. For instance, you may need two or more sinks coupled with a disposal system and a dishwasher in the drain system.
So, there will be more Y-fittings, tees, and drain extensions. This is where things get a bit complicated.
Choose The Right Size Pipe For The Kitchen Sink Drain:
When deciding on the size of the drain pipe for the kitchen sink, you should take into account both the drainage area and the size of the sink.
The diameter of the pipe needed will be determined by the kind of sink being installed as well as its final destination.
A conventional kitchen sink, for instance, calls for a pipe that is 1 1/2 inches in diameter.
But, as we have stated earlier, for a double sink kitchen, 2 inches will be a requirement.
The assessed drainage area distinctly has a huge impact on what size pipe the sink will ask for.
Again, a pipe with a diameter of half an inch will be sufficient for the drainage needs of a small sink.
But a sink with many drainage options will require pipes of a larger size.
Here are the tips to easily decide on the pipe size-
Take A Measurement Of The Diameter Of Your Sink:
Well, this is the first requirement. In order to determine the appropriate size of the drain line in the kitchen sink, you will need to measure the diameter of the sink.
You can either use a measuring tape or your hands to do this task. Whatever the equipment is, measure the diameter of the sink correctly.
Any mistake here may cost you big time.
Secondly, determine the suitable pipe size by calculating it based on the dimensions that you have discovered.
It is imperative that you use a pipe that is sufficiently big to fit within the sink. At the same time, it shall allow for free water to flow through it.
Evaluate The Diameter Of The Pipe You’ll Need In Relation To The Diameter Of Your Sink:
Now is the time to determine the appropriate size of the drain line for the kitchen sink.
Here it is vital to take into consideration both the diameter of the pipe and the size of the sink.
Water will continuously trickle down the drain if the pipe’s diameter is less than that of the sink.
So, you may even consider expert help to secure the system. It might cause the pipes in your kitchen to become clogged, as well as create a mess in the room.
The pipe diameter cannot even be bigger than what the system needs. In that case, water will drain readily.
Even, if an excessive amount of water is released all at once, it may cause the sink to overflow.
To stop water from leaking out of the faucet in either scenario, you shall have to utilize a socket wrench.
The wrench can tighten the faucet bolts if the pipe is larger than the requirement. Or, you can loosen the bolts if the pipe is smaller than the needed size.
Thus, the bolts will fit securely into their respective holes. This will ensure that there are no leaks.
Determine How Long A Section Of Pipe Is Required:
To properly install a new drain for the kitchen sink, you will first need to determine the required pipe length.
To begin with, determine the width of the drain aperture in the sink by measuring its diameter.
To determine it, take a measurement that extends from the middle of the sink to the perimeter of the countertop.
Following that, you need to find the hole diameter by dividing this figure by 2. Lastly, you may use this data to calculate the length (feet) of pipe you have to buy.
As you know already, pipes of this type typically have a diameter of 1 and a half inches.
The most appropriate component for this situation is a reduction bushing with a range of one and a half to two inches. It should work the best.
The smaller diameter end (1.5 inches) should be connected to the kitchen drainpipe, while the larger diameter end (2 inches) should be connected to the main drainpipe outside the house.
A mount sink requires different considerations.
When the sink drain goes beneath this mount sink, the pipe has to attach to the sink underside finely.
So, it is vital to choose a pipe that has a flared connection to fit there.
Precautions For Installation:
You know- selecting a pipe that is appropriate is an important step.
Yes, this is the first thing to ensure when you for the installation of a drain for your lovely kitchen sink.
Though no one likes it, inappropriate size pipes often cause serious trouble during the installation. Shockingly, the chances of future problems also multiply with this.
Let’s assume you have a 1/2-inch pipe for your standard kitchen sink. What will happen here?
The pipe is way too small. So, the water would not be able to escape through the pipe.
There will always be water in the sink when in use. In fact, when you release the faucet at full capacity, water will back up and overflow your sink!
Thus, this will ultimately damage the sink. The walls and flooring would also suffer due to this. Be careful!
To prevent issues like these from occurring, ensure that the pipe leading to your kitchen sink is the appropriate size.
What Kind Of Pipe Does A Sink Drain Need?
Many kinds of pipes may be utilized for a sink’s drain. Also, there is a lot of misunderstanding regarding this among the general public.
The pipe that makes up a sink drain is typically made of plastic or metal.
The dimensions and configuration of the drain will determine the kind of pipe that can be used.
Polyvinyl chloride, what you call PVC, is by far the most popular choice when it comes to piping.
Although not metal, PVC behaves like a metal. You can thread it as you do on metal; you can drill on it and cut it.
PVC is also super flexible. So, you have to go through an unnecessary hassle to shape the pipe conforming to the diameter of the drain.
Perforated Expanded Polystyrene, widely known as PEX, is another favorite for sink pipes.
Multiple layers of styrene foam build up PEX. As a result, it is so durable, resilient, and strong.
So, worth the money as well. The only drawback for PEX is that it is not so flexible.
Set Up The Drainage System Cautiously:
It is necessary to know the full drainage system clearly to choose the pipe size efficiently.
The pap size can change based on various factors. For instance, the drain line pipe may even affect the sink pipe.
So, let’s figure out the others things that may affect the pipe size.
Connection To The Drainpipe In The Kitchen:
The drain pipe in the kitchen sink is connected to the drain. As the drain is under the sink, there is a solid combination of a threaded pipe and sink basin.
The threaded pipe protrudes out from underneath the lock nut. Thus, it works finely to hold the sink basin and drain together.
This pipe serves as a connector for the drainpipe, which threads on it.
Because the pipe has a diameter of 1 1/2 inches, the drainpipes in the kitchen likewise have a diameter of 1 1/2 inches.
That’s why the pipe cannot usually be more or less than 1 ½ inch.
To link both the pipes is a bit complicated process. But with the right equipment, it should not be complex.
Experts suggest using a pure metal or brass-based connection to do this. Attaching the connector at the drainpipe end will connect the two pipes steadily.
To prevent the drainpipe from coming loose, make sure the connection is properly threaded and tightened.
Design And Measuring Of P-Traps:
The P-trap is the next component that you need to pay attention to. This is the plumbing device in the shape of a P that is attached to the drainpipe.
There are two PVC fittings in this trap both of which are U-shaped.
In addition, the fittings have a measurement of 1 and a half inches. On top of that, they directly link to the drainpipe.
All of the pipe sizes must be consistent with one another. All of them are systematically a part of the drain.
This standardization helps to guarantee that the drain runs correctly and avoids clogs from occurring.
Link To The Main Drainage System:
At last, you have to link the p-trap or the sink drain pipe to the primary drainage pipe. This is crucial to ensure the efficiency of the drainage system.
Typically, the diameter of this pipe is 1 and a half inches. Nevertheless, the drainage pipes in many residences are 2 inches in diameter as we have discussed.
To join the pipes properly, you will require reducing bushing. It will secure the ends of the pipes.
The best option in this situation is a decreasing bushing that goes from 1 1/2 inches to 2 inches.
FAQs about pipe Size for kitchen sink drain:
Can I Use A 2-Inch Pipe For The Sink Drain?
Although not common, you can use it for larger sinks. Usually, when you deal with double sinks, 2 inches pipe is necessary. Otherwise, it is a waste of money and can be detrimental as well.
What Happens If You Don’t Vent A Sink?
The waste will not flush out properly as a result. Possible consequences include clogged pipes, backed-up toilets, and other comparable drainage catastrophes.
Does Every P-Trap Need A Vent?
Yes, it is necessary. They prevent the buildup of pressure in your sewer systems by providing an outlet for sewer gas.
In short, to link to the tailpiece, any horizontal extensions (P-trap system included), the pipes have to have the same diameter of either 1 ½ or 1 ¼ inch.
In exceptional situations, rarely would you need a 2 inches pipe.
Because this is the size of pipe that is used in every kitchen, it is preferable to use it whenever making any kind of repair.
It thus lowers the likelihood that there may be issues in the future matching pipes.
So, don’t wander around thinking about what size pipe for the kitchen sink drain you would need. Just consider the tips above and get the job done.