With the increasing popularity of vessel sinks and the do-it-yourselfers who want to know how to install them, I figured it would be beneficial to write a comprehensive how-to article on the complete process of installing one of these fixtures from start to finish. This article / how to guide will be broken up into several steps, allowing you to skip steps that may have already been completed by your plumber or contractor. The journey will begin with the preparation of the raw water supply lines and drain and end with the completed product.
I also HAVE to mention that this is merely a how-to guide and should not be taken as "the lords word". The writer and publisher of this article is not responsible for any mis-installation, misuse, errors or damaged caused by the direct or indirect use of the content in this article. Now that the legal jargon is out of the way, lets begin.
Step 1: An Overview - Choosing The Sink, Faucet And Cabinet
Before you even start ripping apart countertops or ordering a new vanity you must consider your options when it comes to vessel sinks. First and likely the most important is what material, style, color and shape. These items are important because it will allow you to determine the necessary height of the countertop, mounting method and countertop material. Something I am often asked is, "What is the ideal height of a bathroom vanity for a vessel sink?". My answer is usually, "personal preference", but to come to a decision on height you have to consider the height of most of the people who will be using the sink. Small children and short adults will find it uncomfortable if not impossible to use if the sink is to high, and tall people will have to bend over if the sink is to low.
Most bathroom cabinetry for regular under mount sinks are between 30 and 32 inches, plus the countertop. So if you have to decide if it is ok to bring the total height to over 36 inches (since most vessels are between 5 and 6" tall) or if you want to have a more realistic 30-32" total height. You may be in a situation where you do not have a choice, either you want to use the existing cabinetry you have or the cabinet you want only comes in a standard height. In this case you may want to consider recessing your vessel sink to reduce the overall height, which brings us to the two main ways vessel sinks are mounted.
There are essentially two main ways to mount a vessel sink, but to be more specific, there are two main ways to mount a bowl shaped or cone shaped vessel sink with a smooth outer surface that is NOT MADE OF GLASS. If you have a glass sink or square / rectangular / zen / oval sink then you are basically "stuck" with the above counter mounting method. The other method, which is effectively known as "recessing" allows you to lower the sink partially into the cabinet so only a fraction of the sink is above countertop level. This method requires that your sink be a non-translucent material and that the exterior of the sink be very smooth and even the whole way around in order to prevent gapping. The recessed method of mounting also allows for greater stability since the bowl shaped vessel sink is supported all the way around by the countertop, vs. being supported by a mounting ring, the weight of the sink, adhesive and the drain itself (or a combination of these) in the "above counter" method.
For example, if you had a stone vessel sink in a bowl shape with a smooth outer surface that was 16" in diameter, you could have a 10" to 15" exact circle cut into your countertop that the sink would sit in. A 12" diameter hole would leave you a lip about 3" tall (assuming an original sink height of 5.5"). The precision of cutting of the hole is vital, an uneven hole will ultimately leave you with gaps between the sink and the countertop that not only look terrible, but will also allow water to leak into the cabinet if water was ever spilled on the countertop. To illustrate these two methods, please refer to the diagram and the two photos below.
During this process you also have to decide on a faucet for your vessel sink. There are essentially two derivatives of vessel faucets, either a countertop / deck mounted faucet, or a wall mounted faucet. Wall mounted faucets have an advantage that they have a long spout reach, and can effectively be mounted at any height above the sink, but have the obvious disadvantage that they are much harder to change or upgrade in the future or repair in case of failure. If a wall mounted faucet is chosen, the countertop and vanity design holds little bearing, as long as the sink is positioned underneath where the spout will be, you are fine. If you choose a countertop mounted / deck mounted faucet, be sure you leave enough space between the wall, faucet and sink to allow easy access and handle operation as well as spout reach.
Once you have decided on your sink, your faucet, your countertop, your vanity and your method of mounting you are now ready to proceed to step 2.
Step 2: Vanity & Countertop Installation
Step 2 and 3 are interchangeable depending on the style of your vanity and the space you have to work with. If your vanity has a completely open back that will allow you to slide the unit against the wall without coming in contact with any pipes you can do the plumbing legwork first then install the vanity. However if your pipes are coming through the floor under your vanity or are in another configuration that is conducive to installing the vanity first then complete this step first.
The actual assembly of the vanity cabinet will vary from model to model so you should consult the instructions included with your cabinet for assembly information. One thing worth noting however is that you should leave the attachment of the doors until the very end of this entire installation process since it will make accessing the plumbing easier. Once the vanity cabinet is assembled, positioned and fixed to the wall or floor you can begin the countertop installation process.
The countertop mounting method is dependant on the material the countertop is made of, as well as the vanity itself. Natural stone countertops such as granite, marble and quartz can't be drilled through underneath to mount them, so they are often glued down with a special adhesive or clear silicone. Corian and other engineered countertops are usually mounted the same way. Laminate countertops made of press board can either be glued down with an adhesive, or mounted from underneath using screws that attach the countertop to the vanity cabinet. If you use screws, double check the length of them to ensure they wont go all the way through the countertop.
Ideally, the countertop should already have the holes predrilled to accommodate the sink and the faucet (if you are using a deck mounted faucet). You should have at the least positioned the sink and faucet where you want them, and penciled in where the cuts need to occur. In a laminate or engineered countertop such as Corian, the holes can be made after the countertop is mounted, however if a mistake is made in cutting, its going to be a messy job to remove the top and start all over. So in a perfect world, the top should already have the holes drilled for the fixtures.
In general most vessel sink drains have a 1.5" diameter, so if you are using the "above counter method" of vessel sink installation, you simply need a 1.5" hole to accommodate the drain (or whatever size diameter hole your drain is). If you are performing a "recessed mount" installation, you will need a perfect circle equal to a percentage of the diameter of the sink, to allow it to sit snugly in the hole. Remember, only perfectly smooth bowl sinks can use the "recessed method", all other types of vessels need to be mounted using the "above counter method". Next, if you are using a countertop / deck mounted faucet then you need to consider the hole for the faucet itself. The VAST majority of vessel sink faucets are of a single hole design, so usually only one hole will need to be cut. The average diameter mounting hole ranges from 1.25" to 1.5", check the specifications of your faucet to confirm the hole size that is required. All single hole vessel sink faucets are fixed to the countertop from underneath, either by using a locknut or a mounting bracket with screws that tighten it to the countertop, effectively pulling the faucet down to hold it. The two water supply lines are also run through this same hole from the water supply pipes to the faucet.
The photo below shows a vanity being prepped for a countertop installation, beads of silicone adhesive are run around the perimeter of the top of the vanity, and then the countertop is lowered into place. Any excess adhesive is then wiped away with a wet cloth from underneath the countertop. This particular installation already has the holes for the vessel sink drain and the faucet pre-drilled. This installation is using the "above counter" mounting method where the sink sits entirely above the countertop.
The photo below shows another installation using the "recessed method" of vessel sink installation. Note the 12" diameter hole in the middle of the countertop, this will allow our 16.5" diameter sink to sit partially below the level of the counter to allow for greater accessibility and stability.
Step 3: Rough In Plumbing
I am by no means a plumbing expert, but installing a couple of water supply lines for a faucet and a drain with a P-trap is something that pretty much anyone can accomplish if they take their time, have the right tools and have the willingness to learn. For the sake of simplicity and completeness lets say the hot and cold copper pipes are at their roughed in stage, with no connectors or hoses attached. If you have no hot and cold supply pipes, you should be reading "Plumbing 101" or "Plumbing for Dummies" etc to get to this stage before continuing. The photo shown below illustrates everything you should need to complete this installation (except the vanity cabinet, countertop and threaded water supply pipe valves/connectors).
Listed as indicated in the photo:
- The vessel sink
- The vessel sink faucet
- Faucet mounting hardware
- Faucet water supply lines
- Plumbing P-Trap OR S-Trap and drain accessories (ABS plastic)
- ABS Plastic pipe for drain
- Extra strength silicone and plumbing adhesive
- Silicone applicator gun
- Grips and wrenches
- Plumbers tape
- Drain assembly (popup or grid drain, with NO OVERFLOW)
Not shown in the photo above are the supply line valves that may or may not already be installed. If you are working with a new installation, you likely just have copper pipes with end caps to prevent the water from coming out. If this is the case, you will need to attach threaded valves to the pipe to allow the connection of the faucet supply lines. If you have not already done so, TURN OFF THE WATER, both at where the cold comes into the house as well as at the hot water heater. If you are working with an existing installation you either have valves in place already or simply a threaded end cap that will allow the connection of the supply lines. If this is the case you can skip this step all together and move onto sink and faucet installation.
- This photo shows the hot and cold supply pipes as well as the ABS pipe for the drain. Once you water is turned off, you can remove the end caps by cutting them off with a saw (if they exist) and let the remaining water drain into a bucket.
- The valve being used in this installation is a compression fitting and does not require soldering, making the installation easy enough for anyone to accomplish. Start by cleaning the copper pipe with sand paper, making sure its free of debris and uniformly smooth. Attach the nut and compression ring.
- Attach the valve assembly, you may or may not need to use a small amount of plumbers tape between the valve and nut to ensure a tight seal. Hand tighten as much as you can.
- Use grips and go a quarter turn at most to fully tighten the nut to the valve, ensuring a proper fit. You can now repeat this process for the other copper pipe.
Step 4: Faucet Installation
Once your vanity is installed, the countertop is mounted and the water supply pipes are prepared for the attachment of supply lines you can now start the faucet installation. Faucet installation is typically done first when dealing with vessel sinks since its easier to work without a large sink in the way.
The first step is to attach the supply lines to the faucet. As previously mentioned most countertop / deck mounted vessel faucets are a single hole design, with the water supply lines attaching inside the faucet body. Your faucet may have these connectors right on the bottom of the faucet, or in some modular pole type designs, you may have to take the faucet body apart to reach the internal supply line connectors. Shown below on the left is the connection of the steel braided water supply lines to the body of the faucet, make sure these supply lines are good and tight, often hand tightening is enough. Shown below on the right is the faucet supply lines run though the mounting hole in the countertop as well as the faucet base plate which contains a rubber gasket underneath to create a water tight seal. Also shown is the mounting screw and plate which will be attached to the faucet from underneath the countertop.
Now, go underneath the countertop and attach the faucet mounting screw and bracket, ensuring the bracket does not interfere with the water supply lines. After the screw is fully tightened and the bracket is as close to the bottom of the countertop as possible you can connect the water supply lines to the threaded connector on the water supply pipes. Note that in the photo on the right, we had to install supply line extensions because the supply lines were not long enough to reach the water supply pipes.
The two photos below show a different installation using a different vessel sink faucet that has a lock nut mount, which screws to a threaded piece of pipe attached of the body of the faucet. The photo on the left show the connection of the supply lines, the photo on the right shows the tightening of the nut to affix the faucet to the countertop. Once the faucet is mounted, the same process of connecting the supply lines to the threaded connector on the water supply pipes would apply.
Step 5: Vessel Sink Installation
After the faucet has been installed, you can now proceed to the actual installation of the vessel sink. As previously mentioned in this how to guide, there are two different ways to mount a vessel sink. The first is the "above counter method" which is the most popular method and can be used for any shape or style of vessel sink. The second is the "recessed method" which can only be used for perfectly rounded vessel sinks (bowl or cone) that have a smooth outer edge and are made of a solid material such as stone, wood or copper. Transparent glass sinks are not suitable for recessed installation. Additionally, the installation methods described here are applicable directly to stone vessel sinks. Glass vessel sinks and some copper or stainless steel vessel sinks require a mounting ring which may or may not be supplied with the sink to give the sink more stability and to distance it from direct contact from the countertop. This mounting ring is especially important for use with glass sinks, and will not be described any further in this article.
In the "above counter method" the vessel sink is held in place by:
- The drain
- Adhesive between the flat bottom and the countertop
- The weight of the sink itself.
To install a vessel sink using this method, follow the steps below:
- Apply a strong silicone adhesive (or countertop adhesive) to the entire contact patch of the sink. The contact patch is the part of the sink that will actually touch the countertop. If you have a bowl shaped sink, the contact patch will likely be very small, if you have a rectangular flat bottom sink, you will run the adhesive over the entire perimeter of the bottom of the sink. Be sure not to apply this adhesive to close to the edge, because once the sink is applied to the countertop the adhesive will flatten out and will need to have the excess wiped up.
- Position the sink drain opening over the drain hole in the countertop and gently set it down, hopefully being accurate enough to only require a minor positioning adjustment.
- Insert the drain through the drain opening and through the countertop to ensure a proper fit.
- Wipe up the excess adhesive.
The photo below shows the installation of a vessel sink using the "above counter method"
In the "recessed method " the vessel sink is held in place by:
- Adhesive underneath the countertop where the countertop and sink meet.
- The weight of the sink itself.
To install a vessel sink using this method, follow the steps below:
- Position the sink in the opening in the countertop, and make sure its level.
- From underneath the countertop, apply adhesive around the entire perimeter of the sink, ensuring contact between the sink and the countertop.
- Insert the drain through the drain opening and through the countertop to ensure a proper fit.
The photo below shows the installation of a vessel sink using the "recessed method"
Step 6: Drain & Drain Pipe Installation
Now that your faucet and sink are mounted, the very last step to complete the installation is to install the drain and attach it to the drain pipe coming out of the wall or floor. For the sake of completeness lets assume that all you have is a raw open drain pipe with no fittings on it (as shown in the photo below). Even if you are replacing an existing sink, you will likely have to replace the ABS pipe fittings to accommodate the new drain position anyway. If you are lucky enough to have the the drain pipe in a position to allow you to accommodate the new drain then you can complete this installation by slipping the new drain into the pipe and tightening the plastic nut on the trap fitting. Otherwise, you can follow the installation instructions below.
The vast majority of vessel sinks DO NOT have overflows, which means two things, one is that the drain you use has to be without and overflow port, and then second is that if you have a pop-up drain (one that you can close to fill the bowl) you do run the risk of overflowing and flooding if you let the water run with the drain closed. In addition a vessel sink pop-up drain is opened and closed by pressing the top of the piece with your finger, eliminating the need for the drain stopper lever and related parts. If you are using a grid drain on the other hand, you will all but eliminate the risk of overflow and flooding. The difference between the two types of vessel sink drains (a pop-up drain and a grid drain) is that a pop-up drain can be closed to allow you to fill up the bowl, this is useful for hand and face washing, whereas as grid drain is similar to a shower strainer or shower drain, it can not be closed, it will continually let water flow into the drain. Both drains are pictured below.
Before installing the mounting the drain assembly itself, you need to assemble and position the ABS plastic piping that connects the drain assembly to the plastic drain pipe coming of your wall or floor. To complete this you will need:
- Extra ABS piping to extend the pipe from the wall or floor (if its not long enough)
- A coupler to couple the extension pipe and the wall or floor pipe (if its not long enough)
- A P-trap or S-trap. A P-Trap is used if the drain pipe is coming out of the wall, an S-trap if its coming out of the floor. Adjustable is best.
- Additionally you may require an elbow fitting(s) to be able to get the right position. This is often fixed with an adjustable P-trap or S-trap though.
- A female trap adapter with lock nut to attach the physical drain assembly to the ABS drain pipe.
- ABS pipe cement / glue to attach all these components together.
Shown below is a P-trap on the left, and female trap adapter on the right.
- Dry fit all the ABS components, in this case we have attached a coupler, some extra ABS pipe and the P-trap.
- Since the P-trap is adjustable, we can swing it directly underneath of our drain assembly, we then need a piece of pipe to connect the P-trap and the female trap adapter (which the drain will slide into) together. Measure out this piece of pipe, attach the female trap adapter and dry fit.
- Once the dry fit is completed all the components are all cut to size, we can glue them all together with ABS pipe cement. Be sure to thoroughly coat each joint and press the components together to get a tight fit.
- Attach the last piece of pipe and the female trap adapter.
Now that our ABS piping is ready, we can insert the drain, tighten the locknut and complete our installation. The vessel sink drains made by Eden Bath and sold by BathroomVesselSinks.com contain two rubber gaskets to seal the drain from leaking any water. Some of the drains feature a bottom pipe that needs to be unscrewed from the rest of the drain assembly in order to allow the drain to fit through the drain opening of the sink and countertop. This piece is later reattached underneath the counter. To complete the drain installation, follow these simple steps:
- Unscrew the lock nut and remove the lower rubber gasket from the drain. If the bottom most part of the drain (the tailpipe) is detachable, unscrew it and remove from the main threaded drain assembly.
- Insert the drain into the sink from above the counter / inside the sink basin.
- Depending on the drain type, you may need to use plumbers putty first to bond the drain to the sink itself, if this is the case with your drain, proceed with doing this.
- From underneath the counter, reattach the rubber gasket and locknut as shown in the photo on the left below. Insert the tailpipe of the drain into the female trap adapter as shown on the right. These photos shows a recessed vessel sink but the same process applies to an above counter mounted sink, except in the above counter method you will be tightening the rubber gasket and locknut to the bottom of the countertop.
- Tighten the locknut on the drain assembly itself, you may need to hold the drain from above to prevent it from spinning. Make sure the rubber gasket and locknut are as tight as possible (but do not over tighten, or you risk damage to the drain assembly and sink).
- Once the drain assembly is tightened to the sink (for a recessed install) or to the bottom of the counter (for an above counter install), tighten the plastic locknut on the female ABS plastic trap adapter, this will grip the tailpipe of the drain assembly, creating seal.
The very last thing you want to do is turn your water back on and test the faucet and the drain, run it for five minutes to ensure the faucet, water supply lines and drain are not leaking. The installation of the vessel sink and vessel faucet is now complete!
Tricia is the head of sales and marketing for BathroomVesselSinks.com – a leading online retailer of luxury vessel sinks made of natural stone, copper, glass, porcelain and more. The online retailer also offers numerous bathroom and kitchen fixtures and faucets. BathroomVesselSinks.com offers affordable and functional handcrafted works of art that are sure to please even the most discerning home owner. Tricia has written several articles oriented towards helping homeowners achieve their artistic vision within their home.