Pelican Parts Forums - Concrete Counters

Pelican Parts Forums (http://forums.pelicanparts.com/)

- Off Topic Discussions (http://forums.pelicanparts.com/off-topic-discussions/)

- - Concrete Counters - Any Pros Here? (http://forums.pelicanparts.com/off-topic-discussions/535968-concrete-counters-any-pros-here.html)

Quote:

Originally Posted by 1968Cayman (Post 5287734)

That's the way most people recommend doing it, but I'd be stuck trying to flip it and place it with my wife- there would be much complaining and I imagine she would likely drop it at some point during the move.

I figured out what was wrong. The mix was entirely too dry, causing me to put too much mix in (rather than flowing smoothly, it was clumping and wouldn't spread evenly), and my initial material projection was a tad high even though I went through it about ten times. To illustrate how bad the mix was, in two hours I removed the concrete and reset the mold; I'll even be able to reuse the rebar. So I'm out $16 in concrete, $3 in caulk and about 4 hours of labor. Not too steep a price this time.

Assuming you have a desk that would hold the weight (and wouldn't have to reinforce it), the cost of the top would probably be about $90 (mold materials, rebar and concrete). There's a really good book on it by a man named Cheng. The total cost for my ~21 sq ft top was $74 at HD. The actual counter base cost was about $85 for lumber, hardware and Durock.

edit: mold materials might run it up a bit. I'd say a 16' x 3' mold might cost closer to $110 to make but the concrete wouldn't be more than $40.

don't forget labor and transporation. concrete is cheap, but the time it takes to do it is worth lots of money. Just think about how many people it would take to lift it in place. 2 people are not going to be able to lift a 16'x3' top in place. It WILL break in half. It must be just as heavy as a piece of granite. I had to hand carry a piece of granite top into a house once. The installer had 6 guys plus 2 of mine haul it up to the home. I always get the fuch up job site with no access up in the hill somewhere. I was a 4 1/2'X9' counter. You talking about 16' here.

True, but I was under the impression that he was considering it as a DIY project. I consider my time to be absolutely worthless.

Check out this Concrete Counters Forum over at DecorativeConcreteForums. Seems to have a lot of activity over there.

That's a pretty good resource! From the general tone of it, though, I'd imagine they would hate to learn I'm doing it myself. Maybe I could pose as a contractor . . .

Here's the first set of post-pour pics. My father came down Saturday and helped with v2 of the project and it went much better than it had with my previous assistant- not that she wasn't trying . . .

Found a few voids in the leading edge which I'll fill with mortar before polishing the whole piece and framing out the cabinets. The first plan was to have a curved front edge but I decided to go with a straight shot to maximize counter space.

http://forums.pelicanparts.com/uploa...1272913811.jpg

The sink fits perfectly! I am amazed; there were doubts about our ability to acheive a level surface.

http://forums.pelicanparts.com/uploa...1272913919.jpg

After polishing, I have to figure out how to get this machine up there (it will sit in front of the tray on the far left side that drains through a hole in the concrete):

http://forums.pelicanparts.com/uploa...1272914020.jpg

Scott...how did you keep the aggregate from surfacing? What reinforcement? What mix did you end up using? How much did that countertop use?

I ended up using the normal Quickrete mix both times; it took 5.5 80 lbs. bags and about 7 gallons of water for a countertop that's a little over 21 sq. ft with an average depth of 2". There was plenty of cream to cover the aggregate the second time, though there was more water than I'd like (excess water can lead to cracking) but we removed about 2 cups' worth with a paper towel after it had sat for a few minutes (not sure the pros would agree with this, but it worked). Here's a pic of the reinforcement- the rebar was all welded together and the mesh was bent into hooks at one end and wire-tied at the other. It runs around the entire mold (hidden at the front and right edges in pic).

http://forums.pelicanparts.com/uploa...1272920509.jpg

Ended up floating it about an hour after the first batch was in and troweling began about an hour after that (continued for two hours). In hindsight, the trick is to get a nice slurry so that the aggregate doesn't become an issue. The sink plug is the best idea I had over the course of the whole project- it was glued together with blocks in the corners (see pic) so that it could be knocked through the hole when the material was ready for troweling- without worrying about disturbing the concrete.

I definitely think this is a DIY project; you can't be pressured by the idea of the concrete setting- it doesn't happen too quickly and taking our time really made the difference the second time around. Fu's book mentioned something about a 30-minute window between mixing and setting- this might have cause me to work a little too hastily the first time.

edit: also need to mention that we vibrated it with hammers and a paperless palm sander along the edges of the form for about 20 minutes. Even after 15 minutes we were still getting air bubbles but there is only one small void along the lower front edge (a small area, but I'm picky. You can see it in the first finished pick- it's in the very center) that we missed.

Quote:

Originally Posted by 1968Cayman (Post 5286888)

Today I laid v1 of my poured-in-place concrete counter . . . yes, that means there will be a v2, which will require me to shovel the 400 lbs of ruined Quickrete from v1into a bucket and carry it off somewhere .

Thanks for saving me the trouble of my own delusions!!!