Natural beauty, durability, resistance to heat and a sense of permanence are the hallmarks of a granite countertop. But ordinarily solid-stone countertops are a pricey proposition due to the special tooling and installation required. In this story, we’ll show you how to install an alternative—a solid-granite—tile countertop that costs about the same as a professionally installed plastic laminate countertop. That’s for a wide variety of standard granite tile selections, but be aware that you can pay considerably more for premium selections.
We’ll cover preparing a solid subbase of 3/4-in. plywood. Next we’ll add a lightweight tile-backer material called “Denshield” over the plywood. And finally, we’ll lay out and install the 12-in. granite tile surface itself.
The trickiest part of installing stone tile countertops is cutting a crisp, clean countertop “nosing” (or front lip). This difficult task is simple when you use a homemade jig (Fig. B) that’s clamped to a tile saw’s sliding table (Photo 9) to cut perfect 45-degree miters.
To finish off the gap at the backsplash of the counter, we’ve designed a unique, easy-to-install detail (Fig. A and Photo 16) that efficiently uses the leftover tile trimmings from the nosing cuts.
Figure A: Countertop Details
To calculate the number of tiles you need, multiply the lineal footage of 24-in. wide countertops by 2.5. Then add as many tiles as required to cover wider peninsulas or islands and subtract for cooktops, stoves, sinks or other built-ins. Keep in mind that you’ll probably need partial tiles for filling around built-in appliances as well as at least a half dozen more tiles to allow for breakage and miscuts. Have extra tiles on hand; you can always return the leftovers.
In addition to the tile, you’ll need:
- A 25-lb. bag of thinset mortar—gray for dark tiles or white for light tiles.
- A 5-lb. bag of unsanded grout for the tile joints. (Unsanded grout is easier to work into the narrow 1/8-in. wide grout lines and you won’t risk scratching the stone while grouting.)
- A quart of polished-granite sealer to treat the tile and grout surfaces a week or so after grouting the tile (Photo 19). It will help prevent stains from penetrating the porous surface and enhance the natural beauty of the stone.
- A roll of fiberglass mesh tape for taping the Denshield seams (Photo 8).
- A 1/4-in. notched trowel for spreading the thinset (Photo 7).
- A 4-in. or 6-in. putty knife.
- A 2-in. margin trowel (Photo 15).
- A honing stone to soften sharp exposed edges (Photo 13).
- A grout float for spreading and embedding the grout (Photo 17).
- Color-matching caulk to substitute for grout at inside corners (Photo 18).
- Plastic spacers for supporting the backsplash tiles (Photo 16).
At first it might seem intimidating to work with tile that’s made from rock, but it’s not difficult. While you can’t score and snap it like ceramic tile, it cuts easily on a conventional diamond tile saw. In fact, you’ll make all of your cuts that way. Other than that, you’ll use the same tools, materials and techniques needed for ceramic tile except for the grout and sealer types.
In addition to standard carpentry tools, you can rent or buy the tile-cutting saw. If you’re really organized and have underlayment installed and all the tile laid out and planned ahead of time, you can do all the cutting in one day. But if you want to take more time, it may be worth buying a saw, especially if you plan on tiling floors or perhaps a bathroom in the future. Also buy four rubber padded mini-clamps (Photo 9) to hold the tiles to the jig. Steel C-clamps may crack the tiles. But use a couple of small C-clamps to secure the jig to the saw table.
Removing the old countertop can be easy if it’s just screwed to cabinet corner braces (Photo 2) or tough if it’s glued down. One peek inside the cabinets will tell you how it’s secured. If it’s glued down you’ll have to pry it loose with a flat bar. It’s best to pry from inside the cabinets to avoid damaging the finish.
The key to flat, long-lasting tile countertops is a solid plywood base. Thin cabinet sides or corner braces simply won’t provide enough anchorage to hold the plywood flat and stable. After the tops are removed, you’ll have to build up cabinet edges with 1x4 or 2x4 blocking along cabinet backs, ends and areas where plywood splices will fall (Photos 3 and 4).
Cut the 3/4-in. plywood underlayment to length so it splices over blocking using the factory edge of the plywood in the front for straight nosings. Cut plywood to length to fit flush with finished cabinet ends and 1 in. short of cabinets that butt against appliances like stoves or refrigerators.
It’s not hard to estimate your lumberyard purchased materials.
Here’s what you need:
- 3/4-in. plywood underlayment: You’ll need a full sheet of 3/4-in. plywood for every 8 ft. of countertop.
- Tile backer: Buy a 32" x 60" sheet of Denshield (or cement board if Denshield is not available) for every five lineal ft. of counter.
- 1x4 cabinet blocking: Pick up enough 1x4s and 2x4s to line the top of the cabinet backs, cabinet ends and areas where plywood splices will occur (Photos 3 and 4).
- 1x3 backsplash trim cap: Buy enough 1x3 trim lumber that matches your cabinets along with the necessary stain and finish to cap off the finished backsplash (Photos 11, 16 and Fig. A).
- One 1-lb. box of 1-in. roofing nails for nailing down the Denshield.
- One 1-lb. box of 2-in. screws for securing the plywood to the cabinets and the 1x4 to the wall studs.
Rip 3-1/2 in. wide 3/4-in. plywood backsplash strips and screw them to the wall with two 2-in. drywall screws into each stud. Score and snap the tile backer to fit flush with the plywood edges. Span over sink openings and mark the underside with a pencil, then flip it over and cut out the opening with a jigsaw.
Mix and spread a 1/8-in. layer of thinset mortar over the plywood base with a 1/4-in. notched trowel. Embed the Denshield in the thinset and nail it to the plywood with 1-in. shingle nails spaced every 6 in. on edges and every 8 in. across the face. Spread thinset over the backsplash and edges and screw on strips of tile backer with 1-1/4 in. drywall screws.
You’re probably already familiar with cement tile backer board, which is completely acceptable, but a gypsum-based material called “Denshield” (Photo 6) is also a great choice for countertop tile bases. It has a gypsum core like drywall, but the core and the sheathing have been modified to repel moisture and accept a tile overlay with conventional bonding adhesives. If you’ve ever struggled with cutting and installing cement board, you’ll appreciate working with Denshield. It’s lightweight and you cut, snap, rasp and fasten it exactly like standard drywall. It’s sold throughout the country, and home centers usually stock the 32 in. x 60 in. sheets—the best size for countertops.
Splice the Denshield wherever you wish, but keep in mind that all of the splices and the outside and inside corners need to be taped with fiberglass mesh tape and a thin layer of thinset (Photo 8), so avoid using lots of little pieces.
Figure B: Building and Using the Tile Mitering Gig
This miter jig will fit on most tile saws, but it may need alteration for some models. See Fig. B for the cutting sizes of the mitering-jig components. Use any flat 1/2-in. plywood for the jig. A table saw is the tool to use. Cut the parts, then spread exterior-grade woodworker’s glue on the edges and tack them together with 1-in. nails.
Rest the jig on a flat table and clamp a tile to the angled jig surface with the bottom of the tile resting on the tabletop. Then rest the narrow stop block against the top of the tile and glue and tack it to the jig.
Positioning the jig and clamping it securely are crucial for consistent miters. The objective is to get a perfectly even miter that ends right at the edge of the 1/16-in. factory cut micro-bevel on the tile edge. You’ll have to make some fine adjustments. Cut some test tiles with the jig and make the fine adjustments until you’re satisfied. Use rejects for the rear row of tiles with the bad edge against the backsplash.
The jig is set up only for full tiles. If you need to cut bevels on narrower pieces like at countertop ends, mark those tiles during layout and cut them before cutting the tiles to width.
Lay the full tile near the countertop end and adjust its placement by holding the mitered nosing strip against it. Draw a pencil line along the back of the tile onto the tile backer. Mark all of the ends of the countertops and snap chalk lines to mark the back edges of the front row of tile. Cut and finish the backsplash trim board. Nail it to the top of the plywood backsplash board with 8d finish nails spaced every 8 in.
Dry-lay tile (no adhesive) from an inside corner of the countertop, spacing the tiles 1/8-in apart. When you’re working on the sink counter, lay tile from the corner to the sink opening and then begin laying tile from the other end. Cut filler tiles to fit in the middle of the sink where they won’t be so obvious.
Spread thinset with a 1/4-in. notched trowel in front of the line for the front row of mitered tiles. Use a nosing tile to gauge overhangs and embed the tile. Use your eye to keep consistent 1/8-in. grout spaces between the tiles as you lay them. Every few tiles nudge a 4-ft. level against the tile fronts to ensure perfect alignment. Spread thinset and lay the back row of tile, keeping the grout lines aligned with those of the front row. Allow thinset to set up overnight before starting the nosing. Tip: Tape cardboard or paper over cabinet fronts to protect them.
After the tile base is in place, spend some time dry-laying the tile to work out the best-looking top. Inside corners are critical because the grout lines have to align in two different directions. So start at inside corners and work your way towards the countertop ends. Spacers aren’t necessary, because you can easily eyeball the 1/8-in. grout lines for both dry-laying and the actual installation. On the countertop section containing the sink, work from both ends toward the sink. That way, you can custom cut one or more shorter tiles near the center of the sink where they won’t be as noticeable (Photo 12).
Another advantage to laying out the tile ahead of time is that you’ll know if you have enough tiles, and you can mark the backs of tiles (write on masking tape) that need special cuts like narrower tiles at countertop ends or in the middle of the sink. Also mark the tiles that need 45-degree angle cuts and the outside corner tiles.
Tile saws are a watery mess. If you’re cutting in the house, make a temporary tile saw water-containing workstation out of plastic sheeting, 2x2s and a piece of plywood for a splash guard.
When you’re marking your cuts, remember that cutting lines are hard to see or wash off in the tile saw, so mark cuts with masking tape instead.
Nosing and Backsplash Cuts
Cut miters on all countertop front and end tiles (outside corner tiles need miters on adjacent edges; see Photo 11), then cut miters on opposite ends of half that quantity for the nosing. Cut the nosing tiles 2 in. wide. Use the leftover sections for the backsplash.
Here are some of the major things to be aware of so your countertop project will be as smooth as polished tile:
- Before you pull your sink and trash your old counters, get all of your materials together, including the tiles, which may have to be special ordered.
- If you’re replacing the sink and/or faucet, get those in your hands too. After the plywood is down, use the old sink or the template from the new one and lay it out exactly where it goes to make sure it’ll fit between the inside of the cabinet and the outside of the finished backsplash. If clearance is an issue, you can use thinner backsplash underlayment, or, if it comes right down to it, you can even thinset the tile directly to the drywall. But you may have to cut thin tile strips for the back edge of wider counters.
- Make sure you leave plenty of space for appliances. With the stove or refrigerator pulled out, it’s easy to hang counters too far so appliances won’t fit back into their homes between the new countertop edges. Most appliance openings between cabinets are sized exactly, so you’ll have to keep finished edges flush with the cabinet end (Fig. A). You can saw those nosing pieces narrower than the others (Photo 16). Don’t beat yourself up mitering nosings in areas that’ll be hidden.
Other Edge Treatments
Our mitered nosing technique is just one option for finishing the front edges of stone tile countertops, but the truth is that the pros use several different methods. The tile underlayment techniques we show are similar for all three methods shown below. Here’s a rundown of three of the most common edge treatments.
WOOD EDGING: If you’re used to working with wood, this edge is by far the fastest and easiest of all methods. Before installing any tile, rip 1x3 wood that matches your cabinetry down to 2 in. wide, then rout the outside corner with any profile you wish. Leave off the Denshield nosing strip so you can glue and nail the nosing directly to the plywood. Sand and stain the wood then cut it to fit and fasten it to the plywood with construction adhesive and 3-in. finish nails driven into the plywood core. Use tiles and add another 1/16 in. to allow for the tile thinset to gauge how far the wood edge should project above the countertop surface so the wood and the finished tile top will be flush. Finish with three coats of polyurethane. Fill the grout line between the wood and the tile with matching caulk rather than grout or a crack will eventually develop between the wood and the tile.
OVERLAPPING TILE EDGES: As you can see, the front edge of the top tiles overhangs the nosing tiles, so the exposed, unfinished edge needs to be polished (we cut a simple 45-degree chamfer with the mitering jig, but you can leave it square too). This technique works best for marble or limestone tops because the material is soft enough to finish with an orbital sander and progressive grits of 100, 150 and 220 silicon-carbide or aluminum-oxide sandpaper. Begin by installing the countertop tiles first, overhanging the front edges using the same technique described above. Then polish the edges with a 4" grinder fitted with a marble-polishing disk and install the narrow front pieces as we show in the main story.
BULLNOSED EDGES: This is by far the trickiest method because it takes skill to freehand consistent edges with a right-angle grinder. Check around to find a stone fabricator who uses special machinery to bullnose individual tiles. Lay out the tiles as shown in Photo 12, then mark the tiles that require edging. The downside of this method is that you won’t be able to finish your counters for several days while you’re waiting for the fabricator to finish. So it’s a good idea to lay out the tile on the old countertop and take the tile in for grinding before the demolition work starts.
Mix unsanded grout to the consistency of peanut butter and work it into the grout lines with a grout float. Use diagonal swipes across the gaps for good penetration. Sponge off the excess grout with a damp sponge, rinsing it frequently in clean water. After the grout dries overnight, buff off the haze with a clean cotton cloth.
One downside of any tile countertop is the potential for grout to get stained by food or beverages. We recommend two coats of grout sealant applied about a week after grouting.
Also, an ordinary wall backdrop can drag down a beautiful countertop. While all of the tools are at your fingertips, consider tiling adjoining walls. We used various-sized tiles of tumbled and honed (matte finished) limestone along with a metallic tile listel to finish the wall above the backsplash.