Home

(909) 823-7521

D & K Concrete  ©  All Rights Reserved 2016

The following information is offered for reference purposes only.  Consult a construction professional prior to performing any work.  D & K Concrete assumes no responsibility for events resulting from the use of this information.

 Colored Concrete Info

Colored concrete has gained widespread popularity in recent years.  It is commonly used in both residential and commercial applications.  D & K Concrete has been producing high quality colored concrete for over 20 years, in both large and small volumes.  We service some of the best, and largest decorative concrete contractors in the Inland Empire.  


We stock many colors at our facility, but due to the large variety of color pigments available, we suggest you give at least 48 hours notice prior to your pour, in order for us to ensure that we have sufficient quantity of your pigment on hand.


Click here to see a color chart


We suggest that you educate yourself prior to installing colored concrete at your site.  There are many factors that will affect the appearance of colored concrete, many of which will result in undesireable results.  The following is some basic information pertaining to colored concrete.


Site Preparation

As with regular concrete, site preparation is very important to achieving proper results when pouring colored concrete.  The sub-grade should be of a adequate and uniform depth.  The soil should be properly compacted, dampened and free of any organic material.  While the soil should be damp, excess standing water, or muddy conditions should be avoided.  Excessive moisture under the slab  will result in a darker, or “blochy” appearance.  Soil containing alkali requires additional measures to prevent discoloration of the concrete, consult a specialist to determine what additional steps should be taken.  Ensure slabs are properly formed, with correct drainage for you specific application.  Any standing water will have a sustained affect the appearance of the slab, which is especially noticeable with colored concrete. Control joints should be utilized as in regular concrete applications in order to prevent cracks in unwanted areas.


Finishing

For best results, integral (mixed in) color pigment should be used when pouring colored concrete.  “Dusting” colored pigments onto the top of regular concrete is not advised.  

When placing the concrete, the slump should be kept as low as possible within reason.  Excess water in the concrete will cause additional bleed water, which will result in more lime and alkali coming to the surface.  Higher amounts of lime and alkali at the surface, will result in a more pronounced affect of efflorescence.  Efflorescence is the result of the chemical reaction between concrete and water, and is highly noticeable and detrimental to the appearance of colored concrete.  Once the initial slump is achieved, additional water should not be added to the load after unloading has begun.  Adding water throughout the pour will result in the variation of color due to inconsistent water to cement ratios, and additional lime coming to the surface during the chemical reaction.

Timing is critical when finishing concrete.  Knowledge of when and how to place a finish on colored concrete is necessary in order to achieve a more uniform color appearance.  The finish should be delayed as long as possible, while ensuring that adequate finishers are available to get over the entire surface before the concrete sets up beyond workability.  Each load of concrete will set up differently due to variations in conditions.  While calcium chloride should never be used in colored concrete, knowledgeable foremen will have the ability to determine the appropriate use of admixtures to accelerate, or decelerate set times based on existing conditions.  

Prior to final brooming or stamping, trowel the surface completely.  It is important to trowel the surface thoroughly in order to work the lime from the bleed water back into the surface.  Do not wet the finishing tools or use water on the surface when finishing.  It is important to perform the final finish only one time.  The final finish should be applied uniformly, taking into consideration the amount, direction, and pressure of the passes made over the surface.  Slight variations in passes will result in noticeable inconsistency to the appearance of the colored concrete.  If applying a broom finish, do not apply water to the broom.  

Once the final finish has been performed, any reworking will be noticeable.  Any areas that have been “re touched” will vary in appearance from the areas that have not.


Curing

A concrete curing product should be applied to the surface with a sprayer once the concrete is hard enough to walk on without leaving marks.  It should  be applied as directed by the manufacturer in order to ensure the desired results.  Water should never be used during the curing of colored concrete.  Using water will increase the affects of efflorescence.


Efflorescence

Efflorescence occurs when moister moves through concrete, and brings soluble salts to the surface of the concrete.  While prevention is the best remedy, there are steps that can be taken once the finishing and curing processes have been completed in order to help reduce the appearance of efflorescence.

Washing down the slab with water alone will not help eliminate effloresce.  Rinsing solely with water, washes the salts back into the slab, only to reappear once the moisture is brought to the surface by natural conditions in the environment.

The most common solution to the problem of efflorescence is a light acid wash.  Water mixed with a small amount of muriatic acid, and scrubbed with a brush on the surface of the concrete, then washed off at high pressure.

In extreme cases, a light sand blasting is performed in order to remove the efflorescence from the surface.

Once efflorescence is removed, it is important to apply a sealer to the concrete in order to help prevent future movement of water through the concrete, which will result in the re occurrence of efflorescence.

Note: While efflorescence is unsightly, it is  not a structural issue, nor does it generally indicate that the concrete is of inferior strength or quality.  While experienced  contractors and tradesmen will take all possible precautions  in order to prevent efflorescence, it’s occurrence may not always be avoidable due to the nature of concrete, cement and the chemical properties specific to them.


Sealing

Colored concrete should be sealed to help prevent discoloration and the penetration of oil and dirt.  Follow manufacturer guidelines when applying sealer in order to achieve desired results.


Fading

Many factors contribute to the “fading” of colored concrete.  Some pigments are more prone to fading than others, you should consult a contractor specializing in colored concrete prior to selecting the color for your application.  Fading is most often caused by the accumulation of lime and/or alkali on the surface.  Lime is more present at the surface of concrete during the early stages of cement hydration.  In order to reduce the affects of lime at the surface, you should not pour colored concrete if rain is expected the day of, or the day after your pour.  You should also avoid pouring concrete on hot, dry or windy days.