I really can’t remember when we decided that we wanted to go with concrete counter tops in the sun room. Obviously its an option alot of folks are considering these days for many reasons. For us we thought that the look would compliment the barn board and the overall indoor/outdoor feel of the sun room. We also liked that the cost would be reasonable since we’ve tried not to splurge too much on materials and we already went kinda big on the flooring and the club chairs.
A while back Mark started researching how-to articles and videos online and came across the series of posts on Imperfectly Polished. They referenced the apparent Godfather of domestic concrete applications Fu-Tung Cheng. His website offers so much information on the process and possibilities for concrete items in your home, whether you are looking to do it yourself or hire a professional. For the DIY-er, he has several fantastic how-to videos that we, and many others, watched again and again to get a good idea of how the process works.
The first step of the process was to make a template of the area where we wanted the counter tops to sit. This is important because it allows you to create a exact replica of the space, rather than just relying on measurements. To make the templates Mark used 1×4 pieces of pine wood (because they are “straight and cheap” he says).
We knew that we would have to have two pieces of counter top because we would never be able to install one long piece as it would be way too heavy. So the first step to creating the templates was determining where we wanted the seam to be. We decided that it would look best to put the seam in the middle of the two middle cabinets. This would also distribute the weight of the counters most evenly.
Visually the seam may appear to be exactly half of the length of the cabinets but if you look closely you’ll see that the cabinet on the far right in the picture above is wider than the cabinet on the far left, so one side of the counter top will be slightly longer than the other.
Once the templates are made, Mark traced the shape onto the melamine board, which is basically plastic coated particle board. This is ideal for the molds because the plastic coat helps prohibit the concrete from sticking to the mold as well as preventing wood grain from stenciling the hardened concrete. When tracing the template onto the melamine it’s important to remember to turn the template upside down because the bottom of the mold is actually the top of the counter, like when you make a cake in cake pan. *Warning – this will be the first of several baking analogies I will use to describe this process.*
Once the templates have been traced upside down onto the melamine board, it’s time to cut the board and then create the sides. Because A: the template is not a perfect retangle and B: we don’t own a table saw, Mark used his circular saw for this process. To make sure he stayed on his line, he clamped a straight edge to the board to keep the saw from deviating from his trace line.
To create the sides, Mark cut 2 3/4″ strips of the melamine board and screwed them to the bottom/top with decking screws. In order to keep the melamine board from splitting when he screwed the sides in, he pre-drilled holes every six inches and then went back with the screws. The height of the sides is important because it dictates the thickness of your counters. We wanted 2″ thick slabs, which is about as thick as our IKEA cabinets can safely hold, so we add 2″ + 3/4″ (the thickness of the melamine board) to give us molds that were 2″ deep. (By the way, not all cabinets can support the weight of concrete counter tops so it’s important to determine that ahead of time. Luckily, the Internet was able to confirm that IKEA’s cabinets are strong enough to hold them.)
Once the molds are made, the next step is to tape the top edge where the particle board is exposed so that moisture cannot seep in and cause the boards to swell. Then we ran a line of tape about 1/8″ from the seam where each board comes together. This was so that we could then run a fairly straight line of caulk on each of the seams.
Once the caulk was in place, we removed the tape right away. Another pro tip we learned in our research is that using black caulk (instead of white or clear, which is what most people have laying around) will ensure that you don’t miss any spaces and create a airtight mold.
All of the steps above were completed about a week before we actually poured the concrete. In the next post we will cover how that process went. It was not without its ups and downs, and I promise there will be more baking analogies as well!