Poured Island Counter Top

Today I finally poured the concrete for our new counter top over the kitchen island.  Here is a photo of the island with the old formica countertop:

Here is what the island looks like without any countertop

It didn't really matter that there were no supports under the bar area; however; I really don't want to have any cracks in our new countertop so I'll need to add supports.  I'm also going to add a 6-inch bar to the left end.

After removing the old countertop and inspecting the cabinet I found that there wasn't much I had to reinforce.  I used a really inexpensive hard-wood to add some structural strength to the cabinets where I added supports to the bar areas as shown in this photo

Once the reinforcements and the supports were added I installed the 1/2-inch Hardee board.  The Hardee board is the backer to the concrete countertop.  It's made of Portland cement and sand.  

I had to tape and mud only one seam in the island countertop.  The Tape is a glass fiber tape specifically for cement work.  It's similar to the mesh dry-wall tape.  The biggest difference between the concrete mesh tape and drywall tape is the thickness of the tape and the color.

Once the backer board was in place I was able to attach the cement forms I made from strips of melamine.  Here is the countertop with the forms attached to the backer board.

I will admit I made two mistakes.  First I neglected to caulk/seal the underside of the Hardee board and the melamine form.  I also forgot to put tape over the screw holes in the top of the form so we had to be very careful when we poured the cement to prevent it from getting onto the heads of the screws.

While the freshly taped and mudded seams were curing I setup the mixer in the kitchen.  in order to get the mixer high enough to pour directly into the forms I had to use a bunch of the sample slabs I've poured in the past to make a platform to put the mixer on.  In hind-sight, this was not necessary.  We were actually quite lucky that the mixer didn't buck or jump much while mixing or the mixer could have fallen over dumping a load of cement on the floor.

As it was, I didn't seal the forms so there was a lot of leakage we had to clean up.  Instead of pouring one countertop and starting the disassembly of the others, we just poured the one countertop and cleaned up the mess afterwards.  

The picture above shows the freshly poured countertop.  I hadn't yet troweled the cement; however, April has created her river effect in the middle of the countertop.  You can kind of see it but it's covered in a cement slury.  

After the slab has curred for at least three days i'll remove the forms and grind off the excess slurry to expose the aggregate.  We can't wait to see what it will look like.