Welcome to the final chapter of the Making Concrete Countertops Like The Pros series. This is where it starts getting really exciting because we’re just so close to seeing the amazing final product! So hang in for this final stretch. Your beautiful concrete counters are just in reach!
The final steps now are grouting and sealing. Oh, we are so close!
Since step 3, we’ve waited our required 48-72 hours for our concrete slab to cure. (Actually, in class we used a mega huge heat
canon gun overnight to apply direct heat, which sped up the curing process. But if you don’t have one of those, and most of us don’t, then just chill for a few days.)
The amount of time it will take to cure is dependent on temperature and humidity. If your slab is in a hot, humid climate it will cure faster.
Here is our cured slab…
But if you’re wondering exactly how long to wait (umm, 48 hours or 72??) before you can move to the next step, you’ll know your slab is ready when the concrete pulls away from the mold edges like so…
Just like making a cake, right? Well, sort of. …Okay, not really at all. But you know what I mean.
One question I had to ask in class was ‘how come we didn’t lay a plastic cover over the concrete during curing?’ I always thought that was part of the curing process. Ben explained that some people have used that practice to reduce what’s called “curling” of the concrete. Basically, the edges of the concrete can curl either up or down due to a moisture differential between the top and bottom of the slab. You can read more about concrete curling here. But for our purposes, if you flip your countertop over at 48-72 hours max after pouring and lay it on a surface that will allow air to flow around the entire slab (which we’ll do in a minute) so that any additional moisture can evaporate, then you should not have any issues with curling.
Now, if you recall, we built our slab in two pieces, placing some roofing paper along the line where the two pieces connect.
The arrows show where the two sections connect…
Our job now is to separate the two sections so that we can turn over the slabs. To do this, first remove the form sides where the break is. Then gently lift one side of the slab…
Since there’s only a very thin layer of concrete over the roofing paper, the slab will easily break at the right point. Don’t worry about the break looking perfect. This is the bottom of the slab that we’re looking at right now so no one will ever see this view of the countertop.
Next, unscrew the faucet plug…
You may need to scratch out a little of the concrete to get to the screw.
Then it’s time to flip the slabs. When we turn over each slab, we are going to lay each onto polystyrene blocks (remember we used polystyrene to make the sink cut out).
So turn you slab on it’s side and place your blocks down. Then lay the turned over slab onto the blocks. Having these blocks under the slab will to allow air to circulate and dry up any remaining moisture.
Here’s what the first turned over slab looks like…
Notice the arrow pointing to where to start separating the sides of the form. You can use a screwdriver to start separating. Strip all the sides first and then lift the melamine off the top.
Be careful not to drag the melamine on the surface of the countertop. This can cause scratching.
Next, remove the polystyrene sink cut out…
We used a putty knife to cut through it and lift the pieces out, but you can use any sharp object.
Here’s what the sink section looks like…
Lay the slab on the blocks…
Remove the sides of the form and then lift the top off.
You can carefully remove any jagged edges with some medium grit sand paper.
Now, we wait again.
I know, right? Don’t you hate this part!
But you need to wait at least another 24 hours minimum for additional curing once the slab is removed from the form. Ugh.
But the cool part is that you can start to see what your countertop is going to look like. And the grouting and sealing process is going to really enhance your countertop by bringing out the color and that natural stone look.
Once your mandatory 24 wait period is over, you can start finishing your countertop.
The first step in finishing is to apply a coat of Ashby Super Seal which is easily applied with a mini roller.
After applying the sealer, you can actually see all the tiny little pin holes left behind from air in the concrete mix.
Grouting will fill in those pinholes. It’s important to fill the pinholes because if you don’t, they can cause trouble later on by allowing water to get below the sealers.
Wait at least four hours before grouting.
When it’s time to grout (we used Ashby Pinhole Grout Mix), follow the package mixing instructions and add whatever color you choose to the mix. We went with a near black grout color.
You can start the grouting process by smearing the grout onto the deepest veins and pockets.
Then use a damp sponge to rub the grout into all the tiny little pinholes.
Work in small areas at a time.
It’s really hard to see if you’ve filled in all the holes. It will look like you have, but don’t trust that. We rubbed and rubbed and rubbed and when we applied the next coat of sealer we saw how many pinholes we missed. So when you think you’re done, put another five or ten minutes into it.
Once you’re done grouting an area, wipe away the excess grout with a clean damp sponge (squeeze out all the water). Wipe in long strokes applying heavy pressure. Only wipe once with each side of the sponge and then rinse and squeeze the sponge out before moving onto the next area.
Use less pressure when wiping over the veins so you leave as much grout in those areas as possible.
After wiping, let dry. Then use a cotton cloth to remove any haze and grout residue left behind.
Repeat the same process on the sides of your slab. You can also use a small brush on the sides to get the grout into the decorative edges.
Wait a minimum of four hours for the grout to dry. Then apply a second coat of Super Seal.
Wait another four hours. Then apply CounterSeal 3, the final sealer. CounterSeal 3 is a urethane topcoat sealer that provides a stain resistant, scratch resistant, and heat resistant durable finish and is available in either a satin or gloss finish.
Follow the mixing instructions for CounterSeal 3 and then pour it through a nylon paint strainer to ensure a smooth flow.
CounterSeal 3 is applied with a spray gun at a pressure of approximately 40 psi.
And you’re going to need to wear one of these…
I know what you’re saying…Sexy, right?
Yes, wear a respirator!
This stuff stinks, so make sure you can leave the area afterward while it dries.
We didn’t have a mask small enough for my spoiled little
monster angel. So she had to wait in the office until we were done. She was not very happy.
With your spray gun, apply CounterSeal 3 in long side to side strokes
If the sealer goes on with an orange peel texture, that means not enough sealer was applied. But you also don’t want it to go on too thick, allowing it to puddle too deep in low areas.
Here’s what our countertop looked like after spraying on CounterSeal 3…
You’re almost done now. Just let your countertop dry for a minimum of 48 hours before transporting or installing and you’ll be good to go!
Before we get to the final pictures, though, I thought I’d share some of the pieces that the individual students made in class.
In addition to participating in making the countertops while Ben was teaching, each student made their own individual sample piece. That way we all get to go through each step of the process on our own which really reinforces learning.
Our sample pieces were about 18″ by 18″ in size. The students that drove to the class took theirs home. I wish I could have taken my 25 lb. block on concrete onto the plane, but that might have been a little much.
So check ’em out. (These pictures were taken before the final sealer was dry so you will see some white spots on them.)
Most of us used multiple decorative edges on our pieces so we could get an idea of what each looked like when finished.
This one’s mine…
And here is our concrete countertop, installed and all!
Now that is stunning, if I do say so myself!
You can see here where the two pieces of the countertop meet…
To seal that joint, you would grout it and then apply some furniture wax to the cured grout. And the joint will completely disappear.
So that’s it folks. How to make concrete countertops like the pros using the Ashby System.
If you made it this far through the tutorial, you know you want one of your own. So if you’re thinking of remodeling your kitchen and you have the time, I definitely recommend taking the class. Having countertops like these made for your kitchen would costs THOUSANDS of dollars. But you can make your own at a fraction of the cost. And what I really love about these counters is that not only are they simply stunning, but I’ve never ever met anyone that has anything remotely like this in their home.
So, my plan for 2015 is to make a set of these concrete counters for my parents’ home. I’ll be keeping their kitchen makeover on a budget. The plan includes taking down a wall to create an open concept. I’ll also be painting the current cabinets, but will have to reconfigure them since they’ll be losing a wall.
Also in 2015, with the help of Countertop Solutions, I will be laying a stamped concrete driveway at mom and pop’s place too. Countertop Solutions just launched this amazingly innovative product that uses rubber molds to create very large concrete tiles that are then tiled onto a driveway. Here’s a sneak peak of what that looks like…
In the image above, the gentleman is applying a concrete stain. Your stamped concrete can be stained any color.
I plan on using a mold that looks like stone rather than brick. But more on that at a future date.
In the meantime, a great big thanks to Countertop Solutions for inviting me to sit in on their class so I could bring you this really cool concrete countertop tutorial.
That’s all folks!