Concrete with a Marbleized Finish

We are proud of the products we manufacture at Absolute Concrete Colors, Concrete Overcoat (OC) being one of the most versatile and useful. But the true beauty of Absolute’s Concrete Overcoat (OC) combines craftsman skill with pride of workmanship and a never quit attitude. Pat Nordquist is that kind of a man and his work shows it. We are proud to feature some of his work this month.

Credits are given to Paul Groomer Construction for the burnt almond project and we credit Dyna Contracting for the Seattle penthouse project with the graygreen floor. Both colors are custom color matches of Concrete Overcoat (OC) manufactured by Absolute Concrete Colors per owner request. Floor finish design and application is by Pat Norquist of Artisans Concrete. The burnt almond floor is finished with three coats of burnished Dymothane from Tower Industries and the gray green floor is finished with fourteen coats of burnished Shur Brite, also a product of Tower Industries of Lakewood, Washington.

All concrete is irregular, so it lends well to application of Absolute Con-crete Overcoat (OC) using a broad drywall knife or sharp finishing trowel to “squeegee” on like cleaning a window. This “cutting and filling” process has a big impact on the final appearance because the flatter the surface, the more uniformly it will reflect light and that uniformly reflected light is what gives the look of perfection. There is no shortcut for perfection in a floor, any more than there is a shortcut to perfection in an automotive finish. Each step can take multiple coats, whether it is multiple filling and sanding steps or multiple coats of finish. Skipping to the burnished wax phase or other chosen finish too soon, before the floors are perfectly filled with the Absolute Concrete Overcoat (OC), will put the brakes on the final quality. I hope the pictures in the newsletter give you some guess at how truly beautiful they can be. Both of these floors have a lustrous depth that is so very pleasing to the senses.

Pat Nordquist reminds me that multiple coats is not a problem. “I did the 3000 square feet by myself in four days with many coats of Absolute Overcoat (OC) and many sanding passes because it was dry enough to do again by the time I finished one pass.” “Fourteen coats of wax is a little out there,” Pat says, “but that is what the lady wanted and she paid me well to make her happy. My greatest fear is that Byron will die and I won’t be able to get the product. I am asking him to put the formula in his will.” You’ve got it Pat and thanks for the reminder.

The other picture shows a more in-tense marble finish using three colors of Absolute Concrete Overcoat (OC). The base color is Stone Blue OC , followed by Yellowstone and Patient White, an off-white yellow shade of pink used in the Preston home to match the floor finish to a custom enameled pink clawfoot bathtub. Each color is applied and then sanded. The order of color application, how many times a color is applied and how aggressively the sanding is done will govern how the veining and marble character develops. Don’t wait too long to sand. It will get too hard. A number of sealers can be used, depending on the traffic and aesthetic considerations. This example is finished with two coats of SealRite Water Borne mop-on Acrylic Sealer, and toped with six coats of Permashield, a urethane acrylic mop-on water borne sealer, both from Absolute Concrete Colors. Each coat increases the depth and luster. The mop used is a $7 rayon string mop with cut loops.

We will be having classes to introduce the use of Concrete Overcoat (OC) and how to use it in conjunction with Absolute Chemical Stains to create distinct effects impossible with Chemical Stains alone. Be sure to sign up. Pat Nordquist says he can sell Concrete Overcoat all day long to restore floors. We hope he does.
Good luck and happy concreting.
Byron

Some Concrete Stamping Details

Like you, I see a lot of the same problems over and over with stamped concrete. A few simple basics can eliminate most of these problems and elevate the public and builder / owner per-ception of stamped concrete. Just the basics.

No. 1: If color control matters you must use color hardener rather than integral color. There is nothing wrong with using integrally colored concrete and we love to sell the color but color hardener has the benefits of producing more accurate color replication and a denser surface, much more resistant to marring and water penetration. Tests done with Absolute Color Hardeners in Osnabrueck Germany showed that there was virtually no water penetration through the Absolute Color Hardener when cured under controlled conditions for 7 days. Integrally colored concrete would not pretend such capability. The final color is more stable using color hardener than integral color because the color hardener consumes the byproducts of hydration (CaOH)for its own hydration whereas these byproducts remain on the surface of integrally colored concrete as a white salt that masks the color.
Additional advantages using color hardener are your ability to choose light and pastel colors not possible using integral colors and substantial savings for colors like blue or high intensity color because you are not paying for all the color hidden in the concrete matrix.

No. 2: Both powder and liquid release can give good antiquing definition but require some common sense to achieve uniformity. As most of you have experienced, uniform set (often very hard to control on a large job) due to shadows or shaded areas, wind, temperature, travel time and so forth, can make your life interesting very fast. A distinct difference between liquid release and powder release is you will impart significantly better detail to the concrete using antique powder release than using liquid release.

No. 3: In the Northwest USA almost all concrete is specified with air entrainment. Air entrainment can result in at least two considerable issues for the installer and; hence, the discriminating customer. First, there is a natural repelling action between the air entrained concrete and the color hardener. For one thing air entrained concrete holds onto the water. There is little or no bleed to make the concrete accept the dry powder cast on the surface unless the concrete has been fatally damaged by adding too much water at the jobsite. Second, there are electrical forces at work somewhat like the repelling of same charges in magnets. These are highly complex chemical phenomena and I won’t waste your time pretending I can adequately address them. The result can be a poorly bonded skin of color on the surface rather that a good marriage of the concrete matrix with the color hardener. The potential for serious spalls is obvious. You have seen them.

No. 4: When stamping with fixed edge texture mats, especially when the pattern is aggressive, you have all seen tears on the shoulder of the joints. This is unsightly and takes some tedious labor to repair. Left unrepaired it is damaging to the decorative concrete reputation everywhere. (Use Absolute Thin Overlay (OLT) or Absolute Concrete Overcoat (OC) to make prefect repairs.)

If you will go to the trouble to order your concrete with no air entrainment you will see almost 100% of these tears disappear. The reason is fairly simple. The dough-like or sponge-like character of air entrained concrete holds onto the rocks. When you stamp and the rock has to move, the concrete mix moves with it and tears. With no air entrainment the rock will move through the concrete matrix and the concrete will fill after it and you will have a perfect cosmetic joint. I know some of you find that hard to believe. Try it. You’ll like it.

Note 5: My opinion is that you can produce better work if you order concrete with no fly ash. Most engineers will not agree with me. Many installers will. It is more of a feel and a sense from experience than studying the research. Have you ever tried to drill an anchor hole in 50 year old concrete, before all the fly ash fuss? Enough said. You may like the greasy feel when you finish fly ash but it is more prone to leave sweat tracks in your stamp pattern than when there is no fly ash. The jury may still be out on this one. Talk to your peers. You guys (and gals) on the front lines have lots of good information to share. You are wisely saying to yourselves, “we are living in a freeze thaw zone.” Yes, you are, but once you apply Color Hardener, the air is gone from the surface. Also, if you seal the surface, you nullify the purpose of the air entrainment.

Now a note of caution: Don’t take it upon yourself to ignore the specification, thinking the customer will appreciate your effort to present a perfect job. You could end up owning the job instead of getting paid for the job. Also, don’t push real hard to get a spec changed. The engineer or architect will sometimes use that as an excuse to blame you for something else that becomes a job problem because you pushed for changes.

Good luck and good concreting. Byron

Sealer Popped off

Question:
The sealer on my driveway and patio looks terrible. It isn’t just dirty; I can pressure wash that, but there are some spots that look like the sealer is gone, some flaking, and some spots near the garage door that look like the sealer has popped off the surface or away from the surface. What can I do? I spent too much money to have it look like this.

Answers:
You have several things going on between your concrete and sealer and the seasonal changes.

First, you can cause a lot of damage with a pressure washer. Be careful. A stiff brush and soapy water works great to clean the surface. If you are trying to get rid of hard water spots some white vinegar may help. Muriatic acid works also, but start weak, about 2 cups in 5 gallons of water and work up no higher than 8 cups per 5 gallons of water. Always add the acid to the water, not visa versa. Do not use muriatic acid anywhere it can get to the concrete, only where you are cleaning the sealer.

Second, it is very likely that the sealer applied was a solvent borne acrylic with 25% solids. At that level of solids, there is typically not enough solvent available to carry the sealer into the pores of the concrete, so it creates a skin. If you are experiencing popoffs and scaling, I would bet money on it. Where the driveway abuts the garage, there is a wide and repeated temperature change to the surface of the concrete. If it is just a skin, it cannot forever continue to absorb the expansion and contraction, so it pops off. You probably have plenty of sealer on the surface, just poorly bonded to the surface.

Third, and this is a lot of work. Get a face mask with carbon canisters that states on the package that it is for all hydrocarbon solvents. Do not use solvents without the mask and make sure the filters are fresh. Also, make sure there is no ignition source like pilot lights, motors, smokers, etc. Buy some xylene, Depending on how large your area is, you may need five gallons or more. Use an acid brush (about inch and a half bristles) with a handle so you can stand up to work, and pour some xylene onto the surface to work an area two or three feet square. Scrub the xylene around like it was soapy water, keeping it from leaving puddles, until you see bubbles coming out of the concrete. This means the solvent is carrying the reemulsified sealer into the pores and expelling air. When satisfied you have accomplished the mission in the first area, repeat the process.
Fourth. You probably have enough sealer and do not need to seal again. You probably just needed to get the sealer where it belongs. If you think you need to seal again, I recommend you cut the solids as low as 67% with xylene. All you need to do is give it a uniform gloss. Consider using a slip reducing product as well. Sealers can be slippery. Yes, you are right. You are not supposed to cut the solids with xylene because of the increase of solvent into the atmosphere. Sadly, that rule of good intentions has the opposite result. To fix the failure you had to use a whole lot more solvent. And if someone makes the mistake of re-sealing, you will add more solvent to the atmosphere as well. It is always better to do it right the first time and that means the initial sealing should be no more than 15% solids or you will have a fragile skin on top. Just the facts.

Good luck and good jobs!