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Preparing The Countertop

Measure the counter and under the counter to make sure your sink will fit into the countertop and also clear any frame support underneath the countertop. Make sure you have a template for your sink, in order to help you cut the countertop. Templates are usually supplied by the manufacturer and will come with the sink. If you have a template, skip section A and section B below and go to section C. A. If you did not receive a template with your sink and your sink is symmetrically round or rectangular, then follow the next steps... Make sure the counter top is clean and free of any debris. Place the sink onto the counter top where it is to be installed, with the top of the sink facing down onto the counter top. Center it over the sink cabinet. Once you have determined where the positioning of the sink will be, trace around it lightly with a pencil or erasable marking pen, being careful not to damage the counter top. Now remove the sink from the counter top and temporarily place it back in its box or in another safe place. From the pencil mark, measure 1/2" in towards the center of the sink. Follow around the sink tracing and every three or four inches apart make a mark or dot 1/2" in from the original pencil tracing, (one or two inches apart if the sink is oval or round.) Once you have gone around the sink, draw a line and connect the marked dots. Now erase the outside pencil tracing. The smaller tracing you have now made will be the line to use to cut the counter top for the mounting of your sink. B. If you did not receive a template with your sink and your sink is NOT symmetrically round or rectangular, then you will need to make your own template. Place your sink face down onto a piece of clean cardboard. With a pencil, trace a line around the sink. From the pencil mark, measure 1/2" in towards the center of the sink. Follow around the sink tracing and every three or four inches apart make a mark or dot 1/2" in from the original pencil tracing, (one or two inches apart if the sink is oval or round.) Once you have gone around the sink, draw a line and connect the marked dots. Now cut the cardboard on the smaller traced line. Turn the cardboard over and use it as your template to cut the counter top. C. Place the template of the sink on the countertop. Center the template on the sink cabinet. Make sure it is positioned at least 1-1/2" away from the top front edge of the countertop. For deeper countertops you may want to place it further back for aesthetics, but for practicality should not be placed more than 4" from the top front edge. Tape the template in place and using a pencil or marking pen, outline the template. Remove the template, once it has been traced onto the countertop.

Cutting The Countertop

Drill a 3/8" diameter hole on the inside of the outline on each corner if your sink is rectangular. If your sink is round or oval, then drill a hole in front, one in back, one on one side and one on the other side. Use a piece of wood long enough to cover the opening (front to back) by a couple of inches on both sides. (1" wide x 1/2" thick will work fine, but any scrap wood long enough to span the opening will do.) Screw this piece of wood into the center of the countertop piece to be cut out. This will prevent the cut countertop piece from falling through or prematurely snapping off as you complete your cutting. Using a saber saw, insert the blade into one of the drilled holes and start cutting along the inside of the outline until the outline is completely cut, and you are able to remove the cut piece out.

Check the Fit of the Sink

Place the sink in the countertop opening you made, to make sure it fits correctly. If your sink is heavy, get someone to help you. If any adjustment must be made to the countertop it is better to find out now than after you have put sealant on the sink. Once you are satisfied the sink will fit correctly, remove the sink from the countertop.

Install the Faucet and Drain Assemblies

If the sink has faucet holes, then install the faucet. Also install the basket strainer(s). If you have an automated dishwasher, then also attach an Air Gap to the sink, normally installed next to the faucet. If you are installing a garbage disposer, install the disposer flange. If you are installing a bathroom sink, then install the faucet and the pop-up assembly. This will be more easily done at this point as you will have full access to the sink, rather than trying to install the faucet and drain assemblies from below after the sink is installed. If your kitchen sink is heavy, you may not want to install the basket strainers or garbage disposal flange at this point as you may wish to use these as an extra place to hold your sink when installing the sink to the countertop. If your sink is heavy, get someone to help you. To install the basket strainers, disposer flange, or pop-up assembly use a good grade "plumbers putty." Regular plumbers putty is not good for every type of sink. For stone, granite, marble, and other porous surfaces we recommend you use the Amazing Sta Put Ultra Plumbers Putty. Make a bead by rolling the plumbers putty back and forth on a clean surface. Make the bead about the diameter of a pencil. Place the flange upside down and apply the plumbers putty around the underside of the flange. Now place the flange through the drain hole of the sink. Attach the rubber gasket supplied with the basket strainer, disposer flange or pop-up assembly, by placing it around the underside of the flange and sliding it up to the bottom of the sink. The rubber gaskets supplied with the basket strainers and disposal flanges are flat, square cut, and thin. The rubber gaskets supplied with pop-up assemblies are normally beveled and quite thick. These beveled gaskets are sometimes a tight fit and may require some extra effort on your part to slide them against the bottom of the sink. Put the beveled end towards the sink. Slide the paper or metal friction ring up and underneath the rubber gasket to prevent the rubber gasket from moving or twisting as you tighten the nut onto the strainer, disposer or pop-up assembly. As you tighten the nut, any excess plumbers putty will be squeezed out around the lip of the flange. This excess plumbers putty can be removed with your hands and put back into the container as it can be reused for any future use.

Sealing the Sink to the Countertop

Turn the sink over onto a clean surface with the top of the sink facing down. Be careful to not scratch the faucet or put unnecessary pressure on it while applying the caulking to the sink. There are a few types of caulking that may be used. An adhesive caulk (water clean-up type) is the easiest to use and to clean up. Apply a bead around the entire perimeter of the sink close to the edge. Carefully turn the sink over and insert it into the countertop opening. Be careful not to disturb the caulking. Be careful not to scratch the countertop with any of the faucet parts or drain assemblies attached to the sink.

Mounting the Sink Clips

Once the sink is in place you are now ready to finish mounting the sink to the underside of the countertop. Most stainless steel sinks use special mounting clips that hook onto brackets located on the underside of the sink and are tensioned against the underside of the countertop by tightening the bolts against the bottom of the sink with a nut driver. Space the clips evenly around the sink. As you are tightening these sink clips, the adhesive caulking may squeeze out from under the top sink lip. This is okay. Just remove the excess with a clean, soft, damp cloth. If you are using a caulking that is not water cleanable, then wait for the caulk to dry and cut the excess off. For sinks such as cast iron, fire clay or porcelain china no mounting clips are used. Once the sink has been caulked and inserted into the countertop be careful not to move the sink while installing the rest of the plumbing. The weight of the sink will force the caulking to seal the surface between the countertop and the sink. If more weight is needed and the strainers or pop-up assemblies are installed, then fill the sink with water and let sit until the caulking is dry. Once the caulking is dried, the sink will be firmly adhered to the countertop.

Connect the Drains

For Kitchen Sinks: Install the basket strainer(s) and/or disposer flange. (If not already installed.) If you are installing a double sink then the use of a tubular continuous waste kit, end outlet or center outlet, will connect the two drains together. Then connect the P-Trap to the continuous waste kit and to the main drain wall inlet. If you are installing a single bowl sink then just install a P-Trap to the main drain wall inlet. If a Garbage Disposer will be installed on the sink, then install the rest of the disposer to the disposer flange and complete the installation of the drain. If a dishwasher will be used, then the smaller 5/8" hose attached to the dishwasher will need to be connected to the smaller 5/8" diameter inlet of the air gap. Attach the bigger 7/8" diameter hose from the outlet of the air gap to the adapter on the disposal. Make sure the disposer "knock out" plug is removed before attaching the hose to the disposal. Make sure the 7/8" diameter hose is not too long or it may droop. Also make sure this hose is not too short causing it to be kinked. If the hose is drooped or kinked the dishwasher will not drain out of the air gap properly and the water will be forced to exit out the top of the air gap, spewing water into the sink. If a dishwasher will be used, but a disposer will NOT be used, then a tubular branch wye (dishwasher wye) will need to be attached to the drain so the 7/8" hose from the air gap can be attached to the drain. For Bathroom Sinks: Install the pop-up Assembly, if not already installed. Install a p-trap to the main drain wall inlet.

Connect the Water Lines

Before you connect the water lines to the faucet, flush out the water lines. Use a bucket and put the end of the "cold" connector to be connected to the faucet and turn your valve on for a minute to flush out any sediment that may have collected at the angel stop valve while it was closed. Repeat this for the "hot" connector as well. Now you can connect the water lines from the angle stops to the faucet. Turn the faucet on and check for possible leaks in the drain system. Enjoy your new sink!