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Issue #247 - June 1998

Install A Countertop

New cabinets have a powerful effect on a kitchen remodeling project. In terms of layout and budget, few improvements carry more weight. But when it comes to visual impact, countertops can play an equally important role. Using color, texture, and edging details, countertops easily hold their own alongside vast expanses of cabinetry.

With a rainbow of colors to choose from, not to mention the variety of materials available, it’s a sure bet you can get the unique look you want. And, if you’re searching for ways to revitalize your kitchen without financing a second mortgage, paint and new countertops may offer the adrenaline boost your tired old decor needs.

In our case, we added custom countertops to the new Merillat cabinets we installed recently in contributing editor Bob Settich’s kitchen. (Installing Cabinetry)

Many materials were ruled out early because they simply weren’t within the budget Bob and his wife Barbara had set for the project. What the budget allowed was plastic laminate covered countertops. Bob considered going to a local building center to purchase postformed units — those with the backsplash and edging formed in one piece — but in the end opted for site-built countertops. The chance to pick a laminate and add edging of their choice was a big factor in the decision. They also liked the idea of a seamless corner — a feature I’ll explain later.

They selected laminate (4556-60 Scopia) for the counter surfaces, and picked a backsplash (SS profile) and edging (SE style), all from Wilsonart. The edging and backsplash have a thin accent stripe that breaks up the expanse of the counters.

Making it Seamless

Once the Settichs made their decisions, we went to work. The first thing we did was order Medex for the base layer, or substrate. Medex is a water-resistant version of medium-density fiberboard (MDF). It’s stable, smooth, and flat, and we found it easy to trim, despite the clouds of fine dust that billow up when you machine it.

Creating invisible seams with laminate is difficult, and often seams become glaringly obvious over time as water seeps in from repeated washings. So we also ordered a sheet of laminate 5 ft.-wide by 12 ft.-long that let us cover our L-shaped counter with one piece (Countertop Construction View). The leftover piece was used on a small auxiliary countertop.

To fashion the countertop substrate from standard 4 ft. x 8 ft. sheets of Medex, we cut the corner as one section and butt-joined the leg piece to one end. This ensured the corner piece remained flat, and, given the heft of Medex, this two-piece assembly made the countertop easier to handle.

We built up the thickness of the edges wherever necessary by gluing 4"-wide cleats to the underside of the substrate (Figure 1). This assured that the countertops would contact all base cabinet walls to provide adequate support.

I recommend cutting the leg section 2" longer than its finished length to allow for final fitting. And I feel strongly that reinforcing the butt joint with biscuits makes good sense (Figure 2). (But hold off gluing the joint together for now.)

Scribing the Fit

Fitting a countertop is a multi-step process that requires accurate measuring and marking. To be successful, you must reference the substrate to the front edge of the base cabinets so you have the same amount of overhang at all points. At the same time, you want a close fit against the walls.

Lay a section of substrate atop the cabinets, and establish the overhang from the face of the base cabinet (Figure 3). We began with the corner section since it had to fit against two walls (which happened to be slightly out of square).

After aligning the substrate with the base cabinet, we found the point where the substrate and wall were farthest apart, and set a compass to that distance. Then we scribed the substrate (Figure 4).

Don’t worry about minor gaps — they’ll be covered by the backsplash. The main concern is to get the front edge of the substrate parallel with the base cabinet faces.

If you need to remove a lot of material, use a jigsaw to rough out the cut (Figure 5). A belt sander works well for “sneaking up” to the scribe line (Figure 6). Tilt the sander slightly to undercut the edge. This will make it easier to adjust the fit against the wall.

Satisfied with the fit of the corner piece, next we turned our attention to fitting the leg section. In Bob’s kitchen, the end of this piece also butts against a wall, so we couldn’t just cut it to length; we also had to scribe the end for a tight fit.

First, we laid the leg on top of the base cabinets and corner section, butted its end against the wall, and established the uniform overhang. Then we measured the amount the leg overlapped the corner section at the butt-joint. After writing this measurement down, we measured the widest gap between the wall and the other end of the substrate. Then we added the gap and overlap measurements plus 1/8".

Using this sum, we set our compass and scribed the substrate’s end to the wall. By cutting along this scribe line, we also trimmed the leg to the proper length.

When you’re satisfied with the fit, remove the substrate sections and place them upside down on a flat surface. Squirt glue into the biscuit slots and run a bead along the ends to be joined, then clamp the assembly together (Figure 7). In a few hours, turn the substrate over and scrape off any squeeze-out. If necessary, apply wood filler to any low spots, and sand it smooth.

Laying the Laminate

Our laminate arrived a couple of weeks after we ordered it and came loosely rolled up in a cardboard carton. I carefully unfurled it the day before we planned to attach it, laying it flat to remove any “memory” of being curled.

When laminating large pieces, I allow at least two inches of overlap on all sides. This way, I have little risk of misaligning the laminate on the substrate once the contact cement is applied — errors here are tough to undo.

Apply two coats of contact cement to both the laminate and substrate, and use spacer sticks to hold the laminate above the substrate until you have it positioned. After removing the spacers, secure the bond by working over the entire surface with a roller. Trim the excess with a router and a flush-cut bit.

Adding the Edging

Our edging had a tongue for mounting it to the substrate. The tongue fits in a groove that we had to rout in the appropriate edges of the substrate (Figure 8). Because this edging precisely overlaps the countertop laminate, the grooves had to be positioned with dead-on accuracy.

Using the special slot-cutting bit we purchased with the edging, we routed test grooves in scrap to set the router depth. Then we routed the grooves in the countertop.

We cut all edging for the countertop a couple of inches long, and started our fitting process at the inside corner of the “L”. Once we had a tight-fitting miter there, we marked and mitered the opposite ends, then mitered mating pieces for the outside corners. We cut these last pieces to length so they butted against the walls. Apply water-resistant wood glue to the edging, and clamp it firmly in place (Figure 9).

After checking the fit one last time, we applied construction adhesive to the top edges of the base cabinets and carefully set the countertop in place. Braces, wedges, and clamps held it firmly in place overnight (Figure 10).
Before removing the braces, we drilled holes through the cabinet corner braces and drove screws into the substrate cleats (Figure 11).

Finishing Up

The only task remaining was to install the backsplash. Using a ready-made backsplash made this final step a simple process.

Since Bob’s walls were somewhat out of square, we decided to cope the corners instead of miter them — it was actually easier and gave us tighter joints (Figure 12).

The long piece went in first, then we coped the short pieces to fit against it. Even though Bob planned to install a row of ceramic tile above the backsplash, we scribed and trimmed it to get good contact along the wall. We applied a thin bead of adhesive to the back and bottom edge of each backsplash piece, and pressed them into place (Figure 13). We took care to clean up the squeeze-out, and when the adhesive set up, we caulked the seam with clear silicone.

While we wanted to stand back and admire our handiwork, Barbara reminded us that the kitchen still needed the sink and appliances installed. At least she was willing to overlook the plywood underlayment on the floor — for the time being. We plan to wrap up that final phase of this kitchen remodeling project with laminated wood flooring. We’ll be done soon, Barbara. We promise!