American Stonecast Undermount Sink Installation Guide for Laminates

The following guide can be downloaded as a .pdf file for viewing and printing here.

The following is a guide intended to show you how to install an American Stonecast Products undermount sink into a laminate counter top. The easiest way to undermount our sink to a laminate is to select a standard grade, good quality laminate that is not too dark or too high gloss to minimize the potential of telegraphing. Read all of the following instructions before you begin to fully understand all of the procedures to be followed, as well as to make sure you have all tools and materials required.

Not every sink can be undermounted under a laminate. American Stonecast sinks are uniquely suited for this application because they are strong, lightweight, and can be machined without ruining the finish of the sink. If you try this with an inexpensive plastic sink the adhesives may fail and you will be very disappointed.

You will need the following tools and supplies for this type of installation.

Counter top substrate and laminate
Pencil or marker
Clean rags
Denatured alcohol
Sabre saw
High performance contact adhesive
High performance glue, such as methyl methacrylate
Router with bit to cut out laminate
Air or electric sander ( optional )
10 to 20 lb. weight ( optional )
Saw horses ( optional )

Place the sink in the exact location that you want to install it on any substrate that is at least 5/8" thick, and trace around the outside edge with a dark pencil or marker. Make sure there is about a 1/8" gap between the sink rim and your outline mark. Remember that you are only working with the substrate right now, not the actual laminate.

Using a sabre saw, cut out the opening you previously outlined on the substrate, before the laminate is glued to its surface.

When finished, your sink opening should have a nice clean edge.

To double check that your cut is correct, place your sink into the opening. There should be a slight gap between the rim and the cutout.

With your laminate face down, place your substrate onto it, then trace around your sink cutout with a dark pencil or marker.

Take the sink cutout that was removed previously and place it onto the laminate, inside the outline you just made.

Next, while the sink cutout is still in place on the laminate, apply a high performance contact adhesive that is designed for laminating to the back of your main piece of laminate. This should be an even coat that covers all of the exposed area of the laminate. This can be sprayed or rolled on.

You may want a helper for this step. Hold the counter top substrate above the laminate and line it up for placement according to the sink cutout and the sink outline. Do not allow the substrate to contact the laminate until you are certain you have them lined up correctly, then carefully place the substrate onto the glued side of the laminate.

Flip the counter top over so that the laminate is face up, and use a J-Roller to smooth the surface and remove air from between the laminate and substrate.

Using a clean cloth, wipe the outermost edge of the laminated cutout with denatured alcohol. Remove any dust, dirt or particles to ensure a smooth, clean surface for your adhesive.

Using 80 grit sandpaper, sand the rim of the sink to allow a better adhesive bond. You can hand sand, or use an air or electric sander.

Using a clean cloth, wipe the rim of the sink with denatured alcohol. Remove any dust, dirt or particles to ensure a smooth, clean surface for your adhesive.

Use a high performance adhesive designed for attaching sinks, such as a Corian® glue or a methyl methacrylate that can be milled, not a soft glue like silicone. Start running a bead around the rim of the sink. Make sure that you place a solid bead right along the inner bowl rim, as well as additional adhesive in the larger rim areas.

Make sure that the sink is in the proper position, with the back of the sink facing the back of the counter top, and set the sink in place. Gently "wiggle" the sink in the opening to help spread the adhesive.

Set a weight onto the sink to help insure a better bond. Too heavy of a weight may cause a slight telegraphing to show on the laminate show surface.

A secondary bond of a soft adhesive is highly recommended. Run a bead of silicone around the bottom of the sink between the rim and the counter top cutout, bonding the sink to the substrate.

When the adhesive has completely cured, turn the sink over. You may want to lay it between two saw horses for stability. Using a small router bit with a wheel on its tip to guide it, trace the inside rim of the sink to remove the laminate over the sink bowls.

Using an air sander, electrical sander or hand sanding, smooth out any rough edges along the routered edge.

At this point, your installation is complete.

TIP: Depending on how the edge is going to be finished, depends upon when and how you apply the edge treatment. If you are going to self edge with the same laminate, it is best if you apply it to the substrate before you laminate the top so it overlaps both the substrate and the edge laminate.