How to Straighten Bowed and Cupped Laminated Countertops

After seeing the horrendous quality of workmanship performed by "professional" block layers, framers, door installers, trim-work carpenters, and other highly paid tradesmen here in Greensboro, North Carolina, I decided that in spite of the extreme pain being endured from my bifurcated spinal cord, the thought of paying this inept bunch to do the finish work was untenable. Hence, in addition to having to inspect, sand, fill, and re-sand literally every square inch of drywall prior to painting the walls and ceilings ourselves, I installed all the cabinets and countertops (kitchen and bathroom), flooring, fixtures, appliances, and wood trim myself. It is not that we were not willing to pay for quality work, it is that quality work was nowhere to be found.

My general contractor, Mike Curl*, while he is a nice guy and very capable of performing his tasks such as site survey and earth moving, he was very poor at seeing that his subcontractors did a good job. He always dismissed my pointing out the low quality work of others that we were paying in some cases as much as $100 per hour** per employee (many were undoubtedly illegal aliens). I only mentioned the egregious items that I believed would affect the integrity of the structure. Although we always paid the bills of contractors and his company (Curl Enterprises) immediately, it was a 9-month-long battle to get a no-frills 1,150 square foot, single story home, built on a concrete slab, and a detached 1-car garage built. I'm embarrassed to say what it cost us. Someday I will post photos of the truly atrocious work ... but I digress.

The real purpose of this write-up is to show the method I came up with to straighten what were initially very bowed (lengthwise) and cupped (depth-wise) laminate countertops. An Internet search on recommended ways to correct it turned up nothing that could be applied to such extreme misshapenness. Many suggested that with as severely curved as mine were, the best thing to do is to discard them and buy new countertops. That was not an option for two reasons. First, during the COVID scamdemic when the house was built the cost was double what it had been just two years prior. Second, the scamdemic, in early 2022, was still causing a major shortage of building materials, so finding a suitable selection was nearly impossible. It required driving to three separate Lowes locations to get the sections needed.

Having been a woodworker for many decades, there have been a few times I needed to remove warps, twists, or bows from wood surfaces. Cutting a crosshatch pattern on the underside for stress relief and then flattening and bracing the surface always did the trick. Attempting to flatten the countertop by weighing down the edges and screwing the top to the base cabinets would not work because the tension in the curve would likely have caused the laminate on the top to split. Cutting slots in the bottom surface made the less-thick wood easily bend back into a flat surface.

Using a circular saw, the slots were cut about a third of the way through from the bottom, and were spaced 2 inches apart. Those dimensions were really just a guess based on past experience, but they worked perfectly, as can be seen in the photos. I wish I had taken more pictures of the process, but was not planning on documenting it at the time.

Since the countertop needs to be set up about 3/4-inch above the tops of the base cabinets to provide clearance for the drawers, I cut 3-inch wide strips of 3/4-inch project plywood (more plies of wood and better glue than construction plywood) and then glued and screwed it around the perimeter of the countertop and in the areas between cabinets. Doing so resulted in the countertop retaining its flatness while also providing ample surface for driving screws from the base cabinets into the plywood without requiring the use of special attachment brackets. I dare say these countertops are as secure and flat as any I've ever seen - and I've seen many.

Two "L" sections were prepared in the same manner - one to the left of the stove and the other to the right. By the way, epoxy was used along with the special hardware to joint the mitered laminated countertop sections. Doing so assures water will never seep into the joint and cause the wood to swell - a common problem.

By the way, the walls were very bowed in places due to the framers not taking care to select straight 2x4's for the cabinet area. That made both the base cabinets and the wall cabinets difficult to install properly, but I took care to assure the intersections of every cabinet matched perfectly, and ample screws were used to keep frames in alignment and the cabinets firmly attached to the walls. Before the drywall was installed, I put 2x4's horizontally across the walls behind where the cabinets hang to avoid needing to hunt for studs for attachment. Every cabinet has a least two screws top and bottom, neatly and equally spaced, and sunk firmly into either a vertical or horizontal 2x4.

Hopefully if you landed on this page because you find yourself facing the same sort of laminated countertop dilemma, these tips will provide some needed relief. It looks like a lot of work, but compared to the annoyance of trying to force the countertop into place and hope to hold it down with screws, this well worth the effort.

   * Curl Enterprises, Greensboro, NC - building contractor, HVAC installation and service.
** A crew of 3 block layers spent 3½ hours on the foundation of my 24x24-foot garage and charged $1,000 labor. That works out to about $100 per hour per man. I supplied all the material (block and mortar).

Posted May 17, 2023