Acid Stain Concrete - The Process & End Results
Acid Stain Concrete: The Newest Flooring Fad
Acid stain concrete (cement) is the newest flooring fad and has received a lot of attention in the United States . This unique way of coloring uses chemical stains to transform both new and old concrete floors and even ones that already are colored.
The most popular finish is a light-tan. Green and brown follow.
Contrary to the name, acid stain concrete does not rely on the corrosive quality of the acid to produce the resulting color. Instead what happens is that an acidic solution of metallic salts is applied to the surface of the floor. One of the major constituents of concrete is calcium hydroxide, commonly known as "hydrated lime", and it is this that the solution reacts with. The reaction exposes the upper surface thus letting the salts combine with the lime to produce insoluble colored compounds that become one with the concrete. Acid stains can be engineered to be black, blue, green and even brown.
Acid Stain Concrete: The Process
The concrete to be worked on needs to be cleaned of any dirt, oil or stains before any color is added. Newly laid cement needs to sit for at least a month before being worked on and the moisture content should not be above twelve percent.
Once the acid solution is mixed the surface needs to be dampened just before application. Application of the solution needs to be as uniform as possible. For the best result professionals have in the past opted to use a garden watering can. Bubbling should occur indicating that the acid constituent of the solution is opening up the top surface of the concrete. To help the solution work its way in, start scrubbing with a hard bristled brush.
When there is no further sign of reaction, flush the surface with water to neutralize any remaining acid. Check the surface to see the resultant acid stain is uniform and has a texture no courser than say "medium grade sandpaper." If not, you might want to consider applying another coat of acid solution.
To work off any residual pieces scrub the concrete floor with a hard bristle brush and then allow it to dry before vacuuming it.
The end result of the acid staining can be affected by the following variables:
- How much moisture is present at the time - this can be attributed to the age of the flooring.
- The finish that has been applied to the floor before hand.
- How quick the rate of efflorescence with regard the reaction occurs.
- Content of calcium hydroxide present in the cement as well as the presence of other minerals.
The most popular finish at present is a "light tan"; green and brown are the second most popular.