Wednesday, July 24, 2013

DIY Cement Countertops Part II

by Sheila 

Last week I documented the process of creating cement countertops up to the point of pouring them into the forms.  To see the beginning of this project, check out Part I here.   Here are the final steps of the process. A beautiful finished project if I do say so myself! 

This is the slab after the forms are pulled (allow several days for cement to set).  Note the dark caulk which will peel right off, but has provided a rounded edge on the top.  Remember, in this process, the top of the counter is on the bottom of this form.
And then the grinding begins.  You need a wet grinder and starting with a turbo cup attachment, progress through 100. 200, and 400 grit.   You work in a circular motion to polish the cement and expose the aggregate.
Once you have used the turbo cup and the 50 grit polish pad on the grinder, you may need to add a "slurry" to the slab to fill in any small holes you may have.  These holes will be from the small aggregate stones flying out as it is polished and/or from air pockets that were present as it cured.  A slurry is the cement mix you used for the counter with the small stones sifted out.  We used old window screen to sift the dry mix.  Then the cement is mixed with water and rubbed onto the surface of the slab.  It looks like you have just destroyed all your hard work grinding, but this grinds off quickly once it has set (24 hours). 
Here is a close-up of the slab once the grinder has done its job.  You can see the black glass, a little of the clear reflective glass, and the aggregate stones exposed.  The surface is smooth as glass!  Beautiful!
And now for the other three slabs!  Alec uses a squeegee to clean the water off to see how the surface is coming along.
Once the slab is polished it is time to move it in place.  This is when you call in the extra muscle.  We estimate this slab to weigh 300+ pounds.  So I got my Dad and my Granddaughter, Camryn. to help.  She is obviously supervising.

She loves to help!  I think this is where she said "go faster, faster!".
The slabs are in place, and here you can see the seam.  We used a non-sanded grout, as this seam is less than 1/4 inch.  I chose a contrasting darker color that I also plan to use on the backsplash tile.
The sink is epoxied in place and clamped to 2 2x4's to hold it in place.

We taped off the cabinets to protect them from the sealant.  Also clean off all grit or dust prior to sealing with a damp  microfiber towel.
The cooktop side as well.  Protect everything that you don't want "sealed".
The sealer is a product that is specifically designed to seal concrete, sold at the same place as the countertop cement mix.  Follow the instructions carefully to avoid "bubbling" and open your doors and windows for ventilation.
I had a few spots that "bubbled from the sealer, but I sanded them lightly with steel wool.  You can see the shine of the smooth, sealed surface.
Looking good, huh?
Once that is dry (24 hours), a high quality carnaubacar wax is applied.  Wax on, wax off in a circular motion, just like you would do a car.
You can see the glass here in this edge detail.

The new countertops in with the sink and faucet.  You can see the 2" exposed polished edge with this under mount sink.  Looks great!

Here are some of the backsplash tiles I am considering.  I might also just do a simple subway tile, but any of these would work.

This is Alec's bar top prior to install.  Note the sink cut out and the plumbing ready to go.

This is the bar top installed.  The earthy brown is pretty, and I love the glass backsplash with it.  Nice job!
Alec's bathroom vanity - his first cement countertop.   It's a light color with cobalt blue glass.  He also built the vanity cabinet base, framed the mirror and made the light fixture as well. Also installed all the tile. Pretty impressive, huh? 
In summary, this project cost a total of $940, or $21 per square foot.  However, I have left-over materials that I will likely use on other projects; enough cement to do an outdoor bar top and more, grout for my backsplash project, enough glass for another project and left-over lumber.  Cheap granite in this area is about $40 per square foot, but those quotes go higher quickly when you add in the linear feet of finished edges and finished sink cut outs.  I love granite, but as a creative alternative, cement is awesome!   

I really appreciate the help of my Dad (who is always available when the going gets rough), Alec's buddies (who were called in to move slabs around) and David for the faucet install (Thanks Honey - I hate plumbing). 

You can see why I was so glad for Alec's help.  He is an artist!  I could not have done this without his expertise and the time he devoted to this project.  We have worked on many projects together over the years, and we always have fun! I owe him big for this one.  When are we going to demo your kitchen, Son?


  1. That new countertop is really nice.

  2. WOW, this is quite an undertaking! Very impressive and the outcome is absolutely gorgeous. Kudos to you for being able to do something this grand!!!
    xo ~kim