What is Acid Staining?
Acid staining of concrete is a well established process that has been used in industrial and commercial flooring environments for well over 100 years. Concrete Floor Systems is able to provide your business with this aesthetically pleasing decorative concrete flooring option.
Acid stains work by penetrating into the pores of the concrete, where the metallic salts and hydrochloric acid in the stain react with the calcium hydroxide present. This reaction creates a chemical bond that allows the stain to adhere to the concrete, creating a beautiful effect.
Concrete staining with acid stain yields colors that are elegant and mottled that are described by many as “rustic”. Acid stained concrete is very popular in commercial settings like office buildings and upscale retail stores. Acid stained concrete is also becoming more prevalent in higher end homes and condos.
Our Acid Staining Process
1) Suitability of the Concrete Slab
Not all concrete floors will readily accept acid stain and provide you with the desired results. We will balance your desired outcome with the current condition of your floor. For example, acid stain is ineffective at staining large chunks of aggregate.
No matter what the condition of your slab, we can almost certainly get it into a condition where acid staining will be effective.
2) Concrete Moisture Testing
In many cases, we will conduct concrete moisture testing and – if needed – concrete moisture mitigation. We perform RH testing to determine the humidity within the slab. This helps to ensure that your concrete floor can readily accept your chosen color of acid stain.
Concrete slabs with a high moisture content can inhibit the acid staining process and cause serious problems down the road. If your concrete floor has excess humidity, we can install a vapor retarder or a moisture mitigation coating.
3) Apply Acid Stain
Next, we apply the acid stain to your concrete slab.
We ensure that the acid stain is applied evenly by our team to ensure adequate absorption of the acid stain – without excess stain lying on the surface of the concrete floor. Depending on your color requirements, we may apply the stain more than once to achieve your desired results.
The application of acid stain is actually where many do-it-yourselfers can run into trouble. Using too much acid stain is a common error that can lead to issues.
4) Neutralization of Acidic State
After applying the acid stain to your concrete floor, your slab is now – unsurprisingly – in an acidic state. We return your concrete floor to a basic state by scrubbing with specially designed cleaning agents to adjust the pH and to remove any excess stain.
We will test your floor to ensure the proper pH level. We then rinse and return the next day when the floor is fully dried out for the next step (sealing)
5) Sealing Your Acid Stained Floor
To protect your floor from wear and tear, and to preserve the beautiful new acid stain that was applied will use a commercial grade concrete sealer to protect your floor. The sealer protects your concrete from foot traffic and also prevents moisture from penetrating into your concrete slab.
Acid Stain Colors
Acid Stain works a bit different than traditional color dyes and stains where the floor is one solid, consistent color. In other words, a “brown” acid stained concrete floor, won’t be a solid, uniform brown color. Instead, the brown acid stain reacts with the concrete floor and produces, a stunning, varied earthy brown color that looks absolutely amazing.
Typical acid stan colors use variations of browns, greens, blues and reds to provide your floor with an elegant look.
More than One Color?
Different Colors in Different Parts of Your Concrete Floor
Combining Colors Together on Your Concrete Floor
It is possible to combine different actually combine two different colors of acid stain on your concrete floor. To do so, we will apply one color of acid stain followed closely by another acid stain color – either while the first color is still wet – or hours later when the first color has dried completely.
Combining colors can yield somewhat unpredictable results as it may not be a perfect melding of the two colors. Darker acid stain colors tend to dominate lighter colors.
Acid Stained Concrete Floors Pros and Cons
- High End, Elegant Look – While you won’t get a solid color with acid stained concrete, what you do get is an amazing, unique look that will look fantastic.
- Durable – Sealed acid stained concrete floors are highly durable and can stand up to heavy traffic.
- Low Maintenance – Acid stained polished concrete floors are easy to clean and maintain. The lifetime ownership cost of acid stained floors is almost always lower than other alternatives like concrete coatings or tile.
- Color Selection – When compared to concrete dyes, the color selection for acid stained concrete floors is somewhat limited. Most colors are a variation of blue, green, brown, and red hues.
- Somewhat Unpredictable – while you can choose a color for your acid stain, the end result will match the color to some extent, but the patterns will be somewhat unpredictable. While this delivers a beautiful, elegant look, if you’re looking for a solid color with a known outcome, you should consider a concrete dye instead.
Concrete Dyes vs. Concrete Stains: What is the Difference?
There are two main methods for staining concrete: dyes and acid stains. While both give you the same reflective, safe, eco-friendly and non-slip floor there are some differences.
Acid Staining FAQs
What Happens if You Don't Neutralize Acid Stain Properly?
Not effectively neutralizing your acid stain can cause problems with the sealer properly adhering to and protecting your concrete floor.
How Long Does it Take to Acid Stain Concrete?
This will vary based on your project requirements and the condition of your concrete slab. Once the slab is fully prepared and ready to take the acid stain, our crew can generally complete the acid staining process within a day or two.
How Long Does Acid Stained Concrete Last?
Can You Acid Stain Old Concrete?
Yes, you can absolutely acid stain an old concrete slab. Just note that the concrete prep process may be more time consuming and costly to get the concrete floor into a state where it will readily be able to effectively accept the acid stain. For example, if your floor has an old, worn floor coating (like epoxy coating) it will have to be removed prior to the acid staining process.
Is Concrete Acid Stain Permanent?
Is it Better to Paint or Acid Stain Concrete?
Acid Stain is a superior way to change the color of concrete that provides a permanent color change that won’t ever wear off. Commercial, Industrial and retail companies should consider either acid stain or concrete dyes to achieve their ideal floor color.
Painted concrete floors are susceptible to flaking and wearing out and require significant maintenance to keep your floors looking their best.