In our new home, a big thing that needed a modern touch was the countertops. Pink laminate. Not in my house!
If you pour concrete countertops, they’d weight as much as granite or marble. Too much for our RV. What we did was skim coat our existing countertops with thin layers of fine concrete. We used the old counters as a base and the biggest investment for this project was our time. All told, it was less than $100 to do this on every surface in Keystone.
We followed Young House Love’s tutorial how-to post, so give that a read through and commit to memory. I’ll go through the basic steps and add some tips of my own.
The Old Surface
All we did to prepare the old countertops was scratch it up with 60 grit sand paper. It was satisfying to take a decent looking countertop and scratch it to bits.
This is coming from the guy who kept his first iPod in a velvet case to protect the precious metal back from scratches.
The Star of the Show
Ardex Feather Finish. One 10-pound bag gave us 5 thin coats, which was plenty for our entire RV.
When we mixed the concrete, we used one of those little plastic buckets from the paint section of Home Depot. We also made the mix a little wetter than Ardex recommended. This helped spread the concrete a little thinner.
To skim coat our counters, we used the biggest drywall trowel we had, which was a 10 incher. We also used a smaller 4 inch putty knife for the vertical sides of the countertops.
We mixed small batches and worked quickly. From the time you mix the water in, you have about 20 minutes to work. After you mix, pour the mixture onto the surface you’re coating. Even if it will take you a while to get to it, pour it all out. We found that just having the material on the counter, massaging and squishing it every few minutes, kept it supple and ready for action. If you let it sit in the bucket, it will start to dry out and become crumbly within just a couple minutes.
Don’t worry about the concrete bits that stick up; you can easily scrape them off after they dry. Be more careful not to leave any divots or holes in the top coat. Those are impossible to sand out unless you remove lots of material.
About 5 minutes after you finish applying the coat, go back with your damp fingers and work on smoothing out the corners and the vertical sides. The concrete is almost clay-like at that time and you can make your sanding work much easier with some finger work.
In between each coat, we roughed up the dry coat with 60 grit and a sanding block. Scrape off any ridges with a putty knife.
Be careful with the corners. I was a bit aggressive in a few areas and exposed some of the old counter. Not to worry too much. The next coat will cover that hideous counter up again.
On the final coat, do not touch the counter with anything coarser than 220. I hit the last coast with 60 and regretted it. The counters were the perfect shape, but I couldn’t sand those 60 scratches out at all. I had to put another skim coat of concrete on to cover those scratches, and ruin my perfect shape in the process.
The sanding is by far the most time consuming part. I sanded the final coat for over 3 hours. My biceps were numb by the end of it, but I felt like Popeye when I flexed. Hello buff Kevin!
Concrete is a porous material that makes a terrible countertop without being sealed first. If you splashed water on the unfinished surface, your new countertops would soak it up like a sponge.
To seal our counters, we used TK6 Nanocoat. It was the priciest of the options I considered, but it’s completely food-safe, which was important for our countertops. You can make do without a food-safe sealer, but you have to be careful to keep your food away from the surface of your counters. All told, we bought a quart for $40 and it was plenty.
We applied 10 super thin coats of the skim-milk-looking liquid with a microfiber pad.
Overall, we’re pleased with how everything turned out. It’s not a super smoother surface like a professionally polished granite countertop, but it’s close enough for us. The color is perfect, a bit lighter than the wet concrete and a bit darker than the dry, unsealed concrete.
There’s still one unsolved problem though.
I’m going to try resealing those areas with more TK6 Nanocoat.