How to Install a Soapstone Countertop

This traditional kitchen topper is easy for a do-it-yourselfer to install

installing a soapstone countertop
Photo by Wendell T. Webber

Too often the price of granite or engineered stone is out of reach of the average renovation budget. Not soapstone. This traditional kitchen topper is easy for a do-it-yourselfer to install, meaning you could save big on the labor, which usually accounts for half the cost. Available to be shipped nationwide from companies such as M. Teixiera Soapstone, where this counter came from, and starting at less than $25 per square foot, soapstone is a great, inexpensive DIY project.

Relative to other stones, soapstone is soft enough that it doesn't require special tools to machine it. You likely already have what you need to cut and shape it: a circular saw, a jigsaw, a drill/driver, a grinder, and a sander. As This Old House senior technical editor Mark Powers shows in the following steps, installing a new slab will take just an afternoon or two.


Steps // How to Install a Soapstone Countertop
1 ×

Overview to Installing a Soapstone Countertop

 
Step One // How to Install a Soapstone Countertop

Overview to Installing a Soapstone Countertop

overview to installing a soapstone countertop
Photo by Wendell T. Webber

Most countertop installations require making a template and sending it off to wait for the fabricator to return a perfectly cut piece. The advantage to installing soapstone yourself from a raw slab is that you can dispense with the template as long as your space is relatively square. (Of course, a template is never a bad thing, if you want to be meticulous about your work. To follow the process for making one, check out this How to Install a Solid-Surface Backsplash.)

As with any stone, soapstone needs a lot of support underneath it—the more surface area it rests on, the better. Gaps and voids underneath one section could put undue stress on the stone. So the first task in any soapstone countertop installation is lining up the cabinets so all the tops are even and the stone can lay flat without rocking. This is best done carefully, with shims placed under the cabinet feet.

Working the soapstone is an easy proposition—the stone is surprisingly soft because of its high talc content, so it can be cut with woodworking tools fitted with diamond-impregnated blades. However, that powdery talc makes cutting outside a must, with dust mask and eye protection mandatory. Also, soapstone's softness means you need to be careful when carrying it, because it could snap at thin points. It's best to carry a cut slab so the face is vertical, to put the least stress on these places. And since it weighs 20 pounds per square foot, expect to call in a couple of helpers to get your counter in place.

The average countertop will require at least one seam to either join two slabs along a long wall or make a 90-degree corner on an L-shaped counter. It's best to hide these seams in discreet places, like in front of the sink or cooktop, where the least amount of the joint will be visible. Adhesive joins the two parts together and blends in with the seam. To make the joint even stronger, you need to cut small slits or grooves in the facing edges of two mating slabs. This gives the seam adhesive more surface area on which to stick.

You can shape the edge of your stone by rounding it over or just taking off the sharpness using a sander with a rough-grit paper. If you have a router, you can even create a fancier roundover or ogee edge. But in any case, the edges will soften over time, especially around an undermount sink, adding to the stone's rustic feel. Although soapstone naturally darkens on its own, rubbing the stone with mineral oil accelerates the process. Oiling also brings out the stone's natural depth and richness, making it more dramatic.

 
2 ×

Line Up the Cabinets

 
Step Two // How to Install a Soapstone Countertop

Line Up the Cabinets

line up the cabinets
Photo by Wendell T. Webber

Pry off the cabinets' toekick and remove the drawers. Place a 4-foot level across the seam between two cabinets and note which one is sitting lower than the other. Using a hammer, tap a shim under the foot of the lower cabinet until the two cabinets are flush. Also, check that the cabinets are somewhat level, or at least pitch only slightly and only inward toward the sink.

Clamp the cabinets together at the stiles along the drawer openings to hold them in place. Using a drill/driver, screw the cabinets together by driving 2½-inch-long deck screws through the stiles. Continue shimming and leveling the cabinets in pairs this way until all the tops sit flush and even.

 
3 ×

Cut the Soapstone to Length

 
Step Three // How to Install a Soapstone Countertop

Cut the Soapstone to Length

Cut the soapstone to length
Photo by Wendell T. Webber

Measure the distance from one end of the cabinets to the other and add in any overhang where the sides of the cabinets are exposed. Mark this measurement onto the soapstone.

Rest the slab on 2x4s running its length to raise it off the ground and support it. Using a circular saw fitted with a diamond blade and guided by a straightedge, cut the stone to length. If necessary, cut a second piece of stone to fit a longer bank of cabinets or a turn in the cabinets. Also, cut the slabs to match the desired depth of the counters.

Tip: Cover the shoe of the circular saw with masking tape or painter's tape before cutting the stone to prevent scratching it.

 
4 ×

Make the Sink Cutout

 
Step Four // How to Install a Soapstone Countertop

Make the Sink Cutout

make the sink cutout
Photo by Wendell T. Webber

Measure in from the end of the cabinets to determine the positioning of the sink and transfer those measurements to the slab. Make sure there are at least 3 inches left between the cutout and the edge of the stone. Mark the location of the sink cutout (and any other necessary cutouts, such as for a stove top) on masking tape stuck to the surface of the stone.

Using a drill/driver fitted with a 2-inch diamond hole saw, make holes inside each of the four corners of the cutout.

With the aid of a helper, lift the soapstone onto sawhorses. For support, clamp 2x4s underneath the stone in front of and behind the cutout outline. Using a jigsaw fitted with a metal-cutting blade, cut the stone along your marks on the two short sides of the layout.

If you are installing an undermount sink, which leaves the edges of the cutout exposed, smooth them over using a random-orbit sander fitted first with 100-grit paper, then with 220-grit paper.

Tip: After you've made a small groove with the hole saw, stop cutting and wedge an ice cube inside the saw to cool the blade and keep dust down as you drill.

 
5 ×

Brace the Sink Cutout

 
Step Five // How to Install a Soapstone Countertop

Brace the Sink Cutout

Brace the Sink Cutout
Photo by Wendel T. Webber

Before cutting the long sides of the cutout, brace the center piece so it doesn't fall and snap the stone as you work. To do this, cut large notches in opposite corners to accommodate a bar clamp. Put a piece of scrap wood long enough to span the two notches and go past the cutline for the cutout under the stone, and clamp it in place through the notches.

With the brace in place, cut the two long sides. Grab the waste piece of the cutout through the notches, and lift it out.

Using a drill/driver fitted with a diamond hole saw, make holes for the faucet and any other plumbing fixtures that fit directly onto the countertop.

 
6 ×

Prep the Seam

 
Step Six // How to Install a Soapstone Countertop

Prep the Seam

prep the seam
Photo by Wendell T. Webber

Wherever two pieces of stone will meet at a seam, cut a series of 1/8-inch-deep slits along the edge, using a grinder fitted with a diamond blade. Space them about an inch apart, on both faces of mating slabs.

 
7 ×

Cut Slots for the Sink Bolts

 
Step Seven // How to Install a Soapstone Countertop

Cut Slots for the Sink Bolts

cut slots for the sink bolts
Photo by Wendell T. Webber

Carefully turn the slab on edge and prop it up, exposing the underside. Then, mark the stone at the top and bottom of the two sink cutout sides, about an inch away from the edge and the corners.

Using a grinder, cut short, 1/8- to 1/4-inch-deep grooves at your marks. With the wheel in the groove, tilt the grinder sharply to either side to make a small pocket inside the stone. Leave one end of the groove wide enough to slide the head of a sink bolt into the groove.

 
8 ×

Check the Bolts' Alignment

 
Step Eight // How to Install a Soapstone Countertop

Check the Bolts' Alignment

check the bolts' alignment
Photo by Wendell T. Webber

Thread a sink clip onto a bolt and screw on a wing nut. Slide the head of the bolt into the grooves around the cutout and check that the clip will reach close enough to the cutout to brace the flange of the undermount sink.

Remove these bolts and clips, and set them aside before moving the stone.

 
9 ×

Smooth the Cut Edges

 
Step Nine // How to Install a Soapstone Countertop

Smooth the Cut Edges

smooth the cut edges
Photo by Wendell T. Webber

Lay the slab flat again. Using a random-orbit sander with 100-grit sandpaper, ease or round over any cut edges. Then, sand them to a smooth finish with 220-grit sandpaper. Also, sand out any nicks or scratches on the countertop's surface with the same succession of grits.

Tip: You can ease the edge more with the sander fitted with 100-grit paper followed by 220-grit. Or, for a more elaborate edge detail, shape the edge with a router fitted with a carbide bit.

 
10 ×

Lay the Countertop on the Cabinets

 
Step Ten // How to Install a Soapstone Countertop

Lay the Countertop on the Cabinets

lay the countertop on the cabinets
Photo by Wendell T. Webber

Grab a couple of helpers and flip the stone on edge. Leave the clamped 2x4s across the narrow edges around the sink cutout for support.

Carry the stone to the cabinets carefully, on edge, making sure not to hold it at the sink cutout.

Lay the slab into position on top of the cabinets, removing any clamps as necessary. Add the second slab, if necessary, and butt the two together. Check that the two pieces are flush with each other and that both rest fully on the cabinet frame. If necessary, shim the cabinets in the front or the slab itself in the back to make sure the two pieces are flush and well supported.

 
11 ×

Adjust the Wall to Fit the Stone

 
Step Eleven // How to Install a Soapstone Countertop

Adjust the Wall to Fit the Stone

adjust the wall to fit the stone
Photo by Wendell T. Webber

If there are any small bows or bumps in the wall behind the counter, create a channel for the stone using a utility knife. (If you will install a backsplash, you can leave as much as a 1/4-inch gap at the back.)

 
12 ×

Create the Joints

 
Step Twelve // How to Install a Soapstone Countertop

Create the Joints

create the joints
Photo by Wendell T. Webber

To join two slabs together, first pull them apart a few inches. Using painter's tape, mask off the top of the stone along the edges.

Following manufacturer's instructions, mix the two-part adhesive. Using a putty knife, butter the edges liberally on both slabs with the adhesive, forcing it into the slits you created with the grinder. Sweep off excess with long strokes.

Push the slabs back together and reshim under them as necessary. Apply pressure for 5 to 10 minutes. Peel away the painter's tape, and scrape away any excess adhesive from the surface of the stone with a razor.

 
13 ×

Smooth the Seams

 
Step Thirteen // How to Install a Soapstone Countertop

Smooth the Seams

smooth the seams
Photo by Wendell T. Webber

Once the adhesive has set—about 30 minutes—smooth the joint using a random-orbit sander and 220-grit sandpaper until the adhesive blends in and looks and feels flush with the surface.

 
14 ×

Set the Sink

 
Step Fourteen // How to Install a Soapstone Countertop

Set the Sink

set the sink
Photo by Wendell T. Webber

For an undermount sink, squeeze a bead of silicone along the top of the sink's flange. Lay a 2x4 across the center of the sink opening. Position the sink underneath the cutout. Holding it with one hand, thread a bar clamp through the drain hole with the other. Tighten the clamp over the 2x4 enough to hold the sink in place. Adjust the positioning of the sink to center it and create an even reveal all around the opening. Tighten the clamp fully, and wipe away any sealant that squeezes out with denatured alcohol.

For an overmount sink, squeeze a bead of silicone underneath the flange. Drop the sink in place and make sure it is centered and even all around. Push the sink down until it is flush, and clean any excess silicone that squeezes out with denatured alcohol.

 
15 ×

Bolt the Undermount Sink

 
Step Fifteen // How to Install a Soapstone Countertop

Bolt the Undermount Sink

bolt the undermount sink
Photo by Wendell T. Webber

With the sink clamped in place, move under the counters. Install the sink bolts and clips in the grooves and tighten them over the flange. Be careful not to overtighten the nut, which could crack the soapstone. Let the silicone cure overnight before plumbing the sink.

 
16 ×

Apply Silicone Sealant

 
Step Sixteen // How to Install a Soapstone Countertop

Apply Silicone Sealant

apply silicone sealant
Photo by Wendell T. Webber

From underneath the counter, squeeze a bead of sealant along the seam between the stone and the cabinets.

 
17 ×

Oil the Soapstone

 
Step Seventeen // How to Install a Soapstone Countertop

Oil the Soapstone

oil the soapstone
Photo by Wendell T. Weber

Vacuum the countertop surface before cleaning it with denatured alcohol.

Once the alcohol dries, apply mineral oil liberally to the countertop. Wipe off the excess with a clean cotton rag. Continue applying the oil twice a week (or whenever the stone turns light gray) for the first nine months to create a patina.

 
 
 

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