Q&A / 

Concrete Countertops

! Please Read Author's Notes at End of This Column !

DEAR TIM: I am an owner/builder and have been told that concrete countertops might be an economical alternative and would suit the type of house we are building. What are the pros and cons with using concrete as a kitchen or even bathroom countertop? What are the steps one takes to build one? Do you feel the average person can fabricate and install one? Jane Powers, Brisbane, Australia

DEAR JANE: I love concrete because it is such an astounding material. When installed outdoors per industry recommendations and exposed to the full force of Mother Nature, it can last for 40 or more years. Thus it goes without saying that a countertop made from concrete that is indoors where temperatures are almost always 70F might last forever. Well, they can last forever, but you might not like the way one looks after 6 months.

This sleek bathroom countertop is concrete. Although it appears to be a no-brainer, you would be shocked at how much work and expertise goes into creating a masterpiece.

This sleek bathroom countertop is concrete. Although it appears to be a no-brainer, you would be shocked at how much work and expertise goes into creating a masterpiece.

Let's first talk about the economics of concrete countertops. You have a distinct advantage should you decide to make them as you would be paying yourself, not a professional, for the labor. Many of the materials needed to make the concrete countertops are commodity items and are somewhat inexpensive. One or two bags of Portland cement will often be enough for hundreds of square feet of countertop surface. The sand, small gravel and coloring pigments are very affordable. The most expensive component is often the sealer that is used to help minimize liquids and foods from penetrating into the concrete once it is a functioning surface.

But if you had to pay a person to fabricate and install the concrete countertops, you might have a mild heart attack when you discover how expensive they can be. The lion's share of the expense is in labor. Building a concrete countertop is extremely labor intensive and don't let anyone tell you otherwise.

There are at least two ways to build these tops. They can be built in a shop and placed on top of the cabinets or they can be poured and finished right on top of the cabinets. In either situation, the forms that have to be built to create the shape of the tops is something akin to finish carpentry. The forms must be perfect, they must be sturdy and they must not fail during the pouring and finishing process. The forms must also come apart easily so as not to damage the fresh and tender concrete once it has hardened.

Perhaps the two biggest places rookies make mistakes are in the fabrication of the forms and the finishing of the concrete. Both are art forms in a manner of speaking. If you think for a moment you will apply a steel-trowel finish that ends up as smooth as glass on your first try, you are dreaming. Once the skill is learned, it is not hard to do, but the problem is getting to that point.

Concrete shrinks as it cures and dries. These internal forces work to rip apart. Sharp 90 degree bends that you often find where countertops change direction or in sink cutouts can be the source of ugly and random shrinkage cracks. Reinforcing steel placed in the thin tops can hold the concrete together so the cracks do not grow much beyond the hairline size. But who wants cracks in a beautiful countertop?

Once the countertop is finished and the forms are off, you need to seal the surface. There can be a significant wait time until you are allowed to apply the sealer. Concrete, even steel-trowel concrete, is an absorbent material. If the concrete is not sealed, liquids, cooking oils and even oil-soaked pizza boxes can cause ugly permanent stains.

But not all sealers perform well over time. Some can scratch, some are heat sensitive and others require periodic application to help keep the protection levels to a maximum. But even still, I have yet to discover a miracle sealer that protects against all possible stains.

In my opinion, concrete countertops are one of those things that look great in magazine photos and in museums. If I had one in my own home, my kids would have its surface looking like the concrete pavement of Interstate 75 that passes through my town. In other words, the countertops would work, but they would not look as good as many of the other countertop possibilities I know to exist.

The actual process of mixing, pouring, finishing and curing the concrete is critical. Make one mistake in any of the steps and you can have a failure in the surface. To make matters worse, even if you do everything right, you can still have problems. Building and installing concrete countertops is not unlike spending a night at a casino. You just might get lucky and bring home a winner.

The system that probably makes the most sense is the countertop formed and poured in place. If you try to fabricate the tops in another location and transport them, you might crack the tops as you carry or set them down. Concrete is very heavy and the reality of placing a large slab that is L or U-shaped is not realistic. If you do install the top in pieces, you then have to deal with sealing the seams. It is by no means an easy task to create gorgeous tops that look like ones you see in magazine or book photos.

Author's Notes - November, 2004

This column created a significant response from a few builders who sell concrete countertops in their homes and craftsmen that fabricate concrete countertops. Most of the responses I received were filled with emotion and claims that I did not do proper research to tell the real story. The truth is I did. I contacted two of the top concrete associations in the world for the latest facts and technology about concrete countertops.

Guess what? The concrete countertop fabricators are not passing the latest information back up the food chain to the authoritative voices in the industry such as the Portland Cement Association or the American Concrete Institute.

One fabricator in particular hit the nail on the head. Daryl Lucien, President of FormTops Studio told me how he feels about sharing the latest technology with anyone. He wrote this to me:

".....In as much as I do that, I keep much of what I do proprietary. It's my intellectual property and a key to my competitive advantage in the marketplace. Even my employees sign non-compete/non-disclosure agreements or they don't work. I'll say it again, this is a business with one simple rule ... if it was easy ... everyone would be doing it ... and not making any money."



3 Responses to Concrete Countertops

  1. Hi, thanks for the great review. What is the best sealer you have found that holds up best against scratching and stains?


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