Most of the questions I receive on our stone hotline have to do with the proper installation of stone countertops. For this reason, I have decided to include a step-by-step procedure for installing stone countertops. Here is one method, out of many, for installing stone that works well.
- Before unloading the truck let your customer know you are there.
- Take a walk through the house and determine what is the best way to move the countertops into the house. Remember that long tops may have trouble moving around corners, etc., and you need to explore all possible routes.
- Determine which piece you will be installing first. For example it is best to install a kitchen L before you install the island. The island is generally the last piece you install. Use your best judgment and plan how you will move the tops in carefully.
- Next, check the cabinets and make sure they are level and have not moved since you templated them. If they have moved or something has changed, you will need to notify the customer and have them correct the cabinets before you can install the stone.
- If everything checks out, then bring the first piece of stone into the house. The stone should be carried in a vertical fashion. Never carry the stone in a horizontal position. If the stone has a sink or cook top opening then you will need to attach the bars and suction cups. The bars are placed across the stone parallel to one another so they cross over the opening. Next, attach the suction cups over the bars. These suction cups will not stay on the stone for very long. You may get 20 minutes before they lose their suction. If you plan to keep them on longer than this, you will need to recheck the suction cups periodically.
- Once the bars and clamps are in place, carefully lift the stone off the A-frame. This will require a minimum of two people. If the stone is very heavy, it may require three or sometimes four people. When lifting, be careful not to twist the stone. Teamwork is very important when moving the stone. You should know every move the person on the other end is going to make. Be sure to talk to one another as you move the stone to keep in constant communication. To lift the stone, make sure that the positions of your hands match the same position as the other person. For example, if you have your right hand on the bottom of the stone, then the other person should also have his/her right hand on the bottom of the stone. If opposite hands and positions are used, you will be working against one another. In some cases you can use carry clamps. These clamps are designed with handles to make lifting stone easier.
- Carry the stone carefully through the building or house taking small slow steps. If there are any obstacles that are observed as you are walking, make sure to tell the other person so he/she doesn't trip.
- Once you have the stone at the countertop, move the piece so that the back of the stone is resting on the countertop's front edge in a vertical position. You are going to use the front edge of the countertop as a pivot point.
- Once the stone is resting up against the front of the counter, while in unison, slowly pivot the stone so that it is resting on top of the cabinet.
- Push the stone into position on the cabinet, and remove the bars and clamps.
- Get the next stone section and transport and install it in the same manner. Care must be taken when installing additional pieces that you don't scratch the pieces already installed. Do not place one section of stone on top of another. This will surely scratch the stone.
- Once all the pieces are in place, you will need to make sure the pieces and seams are level with one another. If you are installing 2cm material, you will have a subtop made of plywood. If this is the case, you should not need to do much shimming if the plywood is level. If you are installing 3cm material, you will not have a subtop in most cases, and you can get under the countertop and install shims as needed to level the counter. This is especially important around the seams.
- This entire process is known as dry setting. Once all the stone pieces are in place and you are satisfied they are level and properly placed, you will be ready to attach them.
- If you are working with 2cm material you will need to lift each section and apply some clear, 100 percent silicone to the subtop. We recommend using an amount measured by a bead that is approximately 1/8 in. round; the beads should be applied in a wave pattern with the waves approximately 6 to 8 in. from one another. You will need one or two people to hold the countertop up while another person applies the silicone.
- For 3cm material, you will not need to lift the countertop in most cases. Simply go under the cabinets and run a bead of silicone under the rails in the back and the front of the cabinets as well as on any cross rails.
- You are now ready to seam the countertops.
Seaming stone sections
Equipment and material needed:
- Seam setter
- Transparent knife grade polyester
- Color kit for polyester
- Single-edge razor blades
- Denatured alcohol or acetone
- Clean white rags
Once the countertop is in place, you are ready to follow the procedure to level and fill the seams.
- Take the seam setter and place it across the seam. In most cases you will be using two seam setter devices.
- Apply the suction cups by pumping the little pump on each cup until the cups are firmly attached. Lift the seam setter device to see if it is attached. If it is not attached, you may need to clean the top with some acetone or alcohol and try again.
- Once the seam setter is in place, use the leveling adjustments to adjust the stone pieces up or down so that both pieces are level with one another. Run a razor blade or your fingernail across the seam to check if it is level.
- When you are satisfied that the pieces are level, shim under the countertop if there is room to do so.
- With the seam setter still in place, move the adjusting knob so the seam opens up about 1/6 in.
- Take some polyester and add some color to match the color of the granite. In some cases you may not need to add color at all. You can sometimes use clear polyester in place of the transparent, in which case, you won't need to color match.
- Add the hardener to the polyester and use a razor blade, putty knife or popsicle stick to fill the seam with the mixture.
- Once the polyester is filled, close the seam setter by adjusting the knob until the seam is tight. This will force the polyester out of the seam. Take a razor blade and remove the excess polyester. Try to clean as much polyester off the stone as possible. This will make clean up a lot easier once the polyester is set.
- The polyester will take anywhere from five to 20 minutes to set up. Once it is set remove the seam setter.
- Take some denatured alcohol or acetone and clean any polyester residue from the surface. You may need to scrape it with a razor blade if it is on too thick.
- Double check the installation, making sure it is sound.
By following these procedures you should have little trouble performing a proper installation that makes you and your customer happy.
This article is an excerpt from Fred's new book Stone Fabrication Operation and Procedures available at www.shop.ntc-stone.com