# concrete countertops



## Millertyme (Apr 20, 2010)

I only built one bench for the precast form to fit on and it was for the island counter which is 36" x81". I needed a place to build my second mold where the sink will go,so I decided to build a form on the floor. I built a 2x4 platform and shimed it perfectly level.then covered it with 1/2"mdo, which i had hanging around in my basement. Then covered it with melamine panel board.The side walls are 1-1/2" melamine particle board.


----------



## Millertyme (Apr 20, 2010)

the bottom cabinets are the new ones. I didnt buy all the top ones yet. I just wanted to get the bottom ones in so i could do the counters. I bought cabinets with solid plywood carcasses for additional support but when i got them i added more support because there was only a 1/4" panel in the back. I just added 1/2" ply to the back of each cabinet. The island in photo has the old counter top from what used to be a peninsula, it works for now. The island will be 1 pour. The back wall where the window is will be done in 3 segments. for 2 reasons. With a large cutout for the sink i didnt want it to break in transport from my basement...it is 12' long. I also figured that if I screwed up the sink and had to remake it, it would only be a small piece to redo.


----------



## no1hustler (Aug 11, 2010)

Cool, I'll be following this thread!


----------



## redheads55 (Oct 4, 2010)

*Thanks for sharing this!*

This is something I have been considering - I am just in the brainstorming mode for our new kitchen and look forward to following your progress. I have a section of my kitchen which would be perfect for a rounded-off counter and concrete seems ideal!


----------



## What have I done (May 28, 2006)

subscribed- this is something we have been planning on doing for awhile now also. Wife just commented the other day about new countertops....might be time to start building forms.

you pouring finishish side up or down? what is your plan of attack for vibrating the forms and finishing?

GET BUSY :laughing: Can't wait to see another DIY-er's results. Knuckelz on here had some very useful tips! I hope to learn from your project as well :whistling2:


----------



## speedtree (Mar 7, 2010)

I've wondered how possible this was for a diy'er. Keep us posted and I'm curious how the coloring turns out.


----------



## wnabcptrNH (Jan 29, 2010)

How are you going to handle cracking? What type of reinforcing are you going to use?

I know you wanted to get the base cabinets in for the counter tops but putting up the tops now is going to be harder with the bases in the way.


----------



## Millertyme (Apr 20, 2010)

I will be casting the top face down into a melamine form. I have seen people use bagged mix and just add pigment or dyes. I actually did this for some samples. But after using these bag mixes, I think it was quikrete 5000, i realized that I could not get the light tan color I wanted. So I bought some white portland and mortar dye from a local masonry supply. The powder dye was 100 times better than the liquid crap from HD. I also bought some admixtures from Fishstone (an online concrete counter vendor). These additives reduce the need for vibrating and allow you to use much less water in your mix. The less water you use the stronger the concrete will be. The superplasticizer takes the place of the some of the water and allows you to use less water and still get a nice flow.I also added glass reinforcement fibers, vcas prozoloans, and a de-foaming and densifing agent.I added 3/8" rebar and remesh to the form for additional support.


----------



## jlhaslip (Dec 31, 2009)

What is the 'blue' stuff ???
Will you be grinding/polishing the concrete???
Any Sealer???
Vibration can be done using a Random Orbit Sander, an Impact Driver or a Palm nailer.


----------



## Millertyme (Apr 20, 2010)

The blue stuff is painters tape. I used it to keep the caulked edges of my form nice and neat. vibration will be done with a orbital sand and a little shaking of the table.


----------



## Millertyme (Apr 20, 2010)

So i did my 1st counter yesterday. Its was a 18"'x26" piece, so I figured it would be a good piece to start with. I knew I need .4 cubic ft so I cut my formula in 1/2 and just made a 1/2 cubic foot.

I started with carefully weighing all my ingredients, put it all in buckets, then got my mixer ready.

I added my white portland and vcas 1st and let mix for 2 min.
I added the all purpose sand and let mix 3 mins.
I added my dye.
Added a 1/4 of my water with plasticizer and defoamer and densifier.
Added PVA fibers slowly with more water.
Finished off water and let mix for about 8 min.
I then did a slump test with a plastic cup and realized it was too stiff, so I added a few ounces of water.

By the time I got concrete out of mixer it seemed to be stiffening up already. It was tough to screed but was weird because there was a lot of water rising to the surface. It seemed like nothing was really binding. Some of the portland had balled up and the fibers were clumped to it.I tried to press some addition rebar in once it was screeded but it was already too stiff to do this. I let it cure overnight and started to strip my form today at about 5pm.to my suprise it looked GREAT. I will try to get a pic up.


----------



## Millertyme (Apr 20, 2010)

here is the counter straight out of the form. The small piece in the pic on right is my grinded sample that i am trying to recreate.looks like im a little dark in my new piece but its still has alot to cure. I put a piece of plastic to let cure for a day or two to keep it from drying out too fast.


----------



## jlhaslip (Dec 31, 2009)

Looks great.


----------



## no1hustler (Aug 11, 2010)

Cool, what kind of mixer are you using?


----------



## Millertyme (Apr 20, 2010)

I got my hands on a 4 cubic ft Kobalt mixer.I found it on craigslist for $140. It was only 2 months old. It hold up to 237lbs.


----------



## grantala (Oct 7, 2010)

One thing to consider is the moisture content of the sand... if your starting with dry sand, then much of the mix water is being absorbed by the sand, leaving you with a dry mix. To combat this, take the sand prior to mixing and add just enough water to make it 'stick together' when you squeeze it in your hand. Think of the sand that's just right for a sand castle. Not too dry and not too wet. After you get the moisture content of the sand, go about adding your measured component - you should wind up with the desired slump and workability. 

On another note, why no gravel in the mix? Weight? You can achieve a much stronger mix with a 1/2" to 3/4" washed aggregate in conjunction with the sand. 

Good luck with the continued project!


----------



## acerunner (Dec 16, 2009)

very cool. I wanted to try doing my own counters too. but that will be almost last step of remodeling, so it will be a long time. I will be watching this thread. Keep us informed with the products & mixtures u try.


----------



## Millertyme (Apr 20, 2010)

thanks for the tip grantala. I checked my sand it it actually didnt look to dry at all. its in a plastic bag so it seems to keep in the moisture. I didnt use gravel because I didnt use any in my samples. The recepie I have didnt call for any. A basic sand mix, with reinforcing fibers.

I grinded my first piece today which seemed to go well. It looked great when it was wet, but when it dried it seem too light. I also think I should have ground it more. I put it in place on the counter to see how it looked. I liked it , but wifey thought it was too gray. It was supposed to be a tan color. She also agreed ...it need to be grinded more to show more aggregate. 
When I did my sample I forgot to measure how much dye I added.I guess I just did it by eye.Well that bit me in the ass when I did my actual counter. I went to make another sample carefully weighing everything and I noticed my dye ratio that I used in my countertop was about 3 times under what I should have used. that is why it looked too gray. So looks like I will be making a new piece.Oh well. Thats why I started with the small one


----------



## Millertyme (Apr 20, 2010)

i have been having a hard time getting my color perfect. The mix is fine except for my color. What I want is a light tan color. however it keeps coming out slightly gray. it still looks nice but not the color I want. I did a few more samples and they look fine when they are mixed but once i grind them down they look to gray. I am using white portland but when i mix in the sand it makes it slightly gray. i even tried adding some gravel in place of sand. I will see how that one comes out tomorrow.


----------



## wnabcptrNH (Jan 29, 2010)

Millertyme said:


> i have been having a hard time getting my color perfect. The mix is fine except for my color. What I want is a light tan color. however it keeps coming out slightly gray. it still looks nice but not the color I want. I did a few more samples and they look fine when they are mixed but once i grind them down they look to gray. I am using white portland but when i mix in the sand it makes it slightly gray. i even tried adding some gravel in place of sand. I will see how that one comes out tomorrow.


After you grind them are you washing the samples? Are you sure the dust isnt making them look grey?


----------



## Millertyme (Apr 20, 2010)

it does look better when it is wet.but still not the desired color. Im using solomon mortar color. It seems I either add to much or not enough. I think the dye is too dark and i want a light color. If i only add a little bit though it comes out fine...at least before it dries. I add more on the next sample and its too brown. Maybe ill try a lighter dye.


----------



## Millertyme (Apr 20, 2010)

well i finally got my color right and poured on saturday. I only did half of what i had to do. I did encounter a few problems though. For some reason my mix was hardening too fast once i got it in the form i could barely spread it around, I had maybe 10 min to get it into the form after it came out of the mixer. This was a problem seeing i had to do 3 batches. Once the form was filled, i wanted to screed the top of it but it was difficult because it was already getting hard. the rocks in the sand seemed to rise to the top a bit and it was like scraping cured concrete. The weird part was that there was still a lot of water on the top and it was pouring over the sides. it seemed like the water rose to the top as the mix below was getting hard. i only used 12.5lbs of water for 130lbs of portland and sand which is just over 10% water. the mix did flow nice as soon as it came out of mixer but the water seemed to seperate from the mix pretty fast. Did I use too much superplasticizer?I used 90ml for 130lbs. which the mix called for 50-140.


----------



## speedtree (Mar 7, 2010)

*concrete expert*

Maybe you've already done this but talk to someone who does concrete for a living and they could probably analyze some of the symptoms you are encountering.


----------



## What have I done (May 28, 2006)

any pics of your 1st section?


----------



## Millertyme (Apr 20, 2010)

the 1st picture was my 1st attempt. The mix wasnt right. I used too much plasticizer. way too much. it caused seperation in my mix.you can see in 3rd pic the stain that was left from water getting trapped under the hardening mix. I tried grinding it out but it didnt work. I remade the mold and made another piece today. i cut my plasticizer in half and used less water. the mix looked a little dry at first but it came out perfect.unlike last time, water wasnt pouring out of my mold.I was even able to trowel it smooth. The first time I couldn't do this because it hardened so damn fast. The last pic is the freshly poured mix.


----------



## MisterPG (Nov 25, 2009)

Subscribed! Keep the detailed posts coming, Millertyme... I'll be working on my own counter tops sometime this winter, and the more armed with info, the better!


----------



## Millertyme (Apr 20, 2010)

Well finally here are the pictures of my countertop done ,sealed and in place...i am satisfied


----------



## STL B. (Oct 29, 2010)

Great job it looks fantastic I love concrete counters now it's time for Q&A. My first question is: What resources did you use for info for this project and did you buy any books or videos?
second ?: What psi is the mix if you know? I'm sure I'll come up with more ?s later cause I am hooked on these counters and would love to try them one day. I have seen 3 methods 1) sack or truck mix poured in place, nice and rustic looking. 2) poured like you did through and through all the same mix and ground or polished, looks like granite or terazzo. 3) is the one mike rowe did on dirty jobs it was sprayed with texture sprayers like for popcorn ceiling. They sprayed several colors to a fairly thin layer then fill the rest with a special counter top strenth mix I would guess the core mix would be cheaper, this method looks like the nicest marble I have ever seen and it makes me drool. Anyway they look sweet you should be proud I am looking forward to learning more.


----------



## Millertyme (Apr 20, 2010)

STL B. said:


> Great job it looks fantastic I love concrete counters now it's time for Q&A. My first question is: What resources did you use for info for this project and did you buy any books or videos?
> second ?: What psi is the mix if you know? I'm sure I'll come up with more ?s later cause I am hooked on these counters and would love to try them one day. I have seen 3 methods 1) sack or truck mix poured in place, nice and rustic looking. 2) poured like you did through and through all the same mix and ground or polished, looks like granite or terazzo. 3) is the one mike rowe did on dirty jobs it was sprayed with texture sprayers like for popcorn ceiling. They sprayed several colors to a fairly thin layer then fill the rest with a special counter top strenth mix I would guess the core mix would be cheaper, this method looks like the nicest marble I have ever seen and it makes me drool. Anyway they look sweet you should be proud I am looking forward to learning more.


I found the web to be the bulk of my research. I bought Cheng's book and video and pulled some info out of there as well.The guys in the Concrete Counter Forum were very usefull as well. Those guys really know there stuff. They are the reason I went away from the premixed stuff. By making it yourself you have better control of ingredients and it keeps cost down. I bought most of my stuff from Fishstone which is an online vendor.I do not know the actual psi of my mix but i am sure it is way beyond 5000.

The stuff you saw on tv might have been GFRC (glass fiber reinforced concrete) it is very strong and very lightweight. looks like a fun thing to try, but I would need a few more tools for that.

One more note. If anyone is pushed away by the fact that they think concrete counters are too heavy...dont be. I well overestimated this part. They were heavy but no heavier than granite. My 3'x7' island was carried in the house by just me and a friend.


----------



## pyper (Jul 1, 2009)

Awesome thread. I wanted to make concrete countertops by my wife vetoed the idea and we went with corian instead.

I bought this book, which seems to have enough details on the process, though I never did it:

http://www.tauntonstore.com/concrete-countertops-fu-tung-cheng-070599.html


----------



## DSeel (Feb 10, 2011)

Millertyme, looks really great! I just got done making a white concrete counter with inlaid glass as a vanity top for my bathroom. Now a friend wants me to make her a tan one for her bathroom. I was just wondering, what was your final "recipe" for the concrete mix?

Thanks!


----------



## Millertyme (Apr 20, 2010)

here's what i used for 1 cubic ft

50lbs of all purpose sand
45lbs of pea gravel (3/8 and smaller)
32lbs of white portland (tough to find around here)
8lbs of vcas pozzolans
20-30lbs of optimum 380 premium superplasticizer 
40-50ml c-64 defoaming and densifying admixture
10 lbs of water
150g pva 8m fibers
5 ounces of tan mortar color (next time i will use concrete dye that is less concentrated)
3/8" rebar
200g silver flakes and 200of gold flakes for some sparkle
eap sealer by kinloch usa (awesome stuff well worth the money)


----------



## FiremanRon (Jul 14, 2011)

*Concrete countertops*

I am knee deep in the concrete countertop project myself. I have been using a quikrete countertop concrete product. I have been very happy using the one bag has it all, process. I've just made a four bag pour mixing all four bags by using the "flip" method. (One bag at the a time) Get a mixer!!! This is my biggest countertop. I've had no problems with the mud drying out at all. I've been able to find fairly good consistency in the color using slurry with color. I have not had good luck with consistent color adding color while mixing concrete. (Using dark).


----------

