A white dusty film forms on concrete floors due to various reasons and it makes them look unattractive and dirty. This is called chalk or dust. If you suspect concrete dust is the reason your floor looks dull, verify it by swiping a broom across the surface or even your finger. Concrete dust lifts up easily. Another indication is if the floor often appears dusty even if there is only light traffic in the area.
Causes of Concrete Dust
The presence of concrete dust indicates that the surface is weak. This is often due to finishing the concrete surface while bleed water is still present. Poor setting of cold concrete during humid conditions is another cause of the concrete dust. Carbonation occurs in areas that are not well-ventilated, and, therefore, chemical reactions may cause dust particles. Curing time is vital when laying a strong concrete surface. If the time was insufficient, the surface is prone to the dust. Sometimes weather conditions, such as snow, ice or heavy rainfall, causes the concrete to freeze before it cures adequately and this is a cause of the dust as well.
Using Concrete Coatings
Covering your concrete with a coating prevents the dust from occurring. An epoxy sealer is effective for preventing the white powdery substance. Other coatings include paint specifically formulated for covering concrete and latex formulations. It is vital that you follow the directions on the label for the product to effectively prevent the white dusty residue. Talk to the concrete company who installed the floor to determine the best time to apply the coating.
Chemical Floor Hardener
Treating the concrete with a chemical floor hardener is one product you can put on the concrete floor to prevent the presence of dust. These are available at concrete, home supply and hardware stores. Look for hardeners that contain magnesium fluosilicate or metallic zinc, as stated by the National Ready Mixed Concrete Association. Other effective chemical hardeners contain sodium silicate.
Cleaners That Prevent Dust
Clean your polished concrete with a solution that is formulated to restore the shine and leaves behind a film that repels dust and dirt. This is appropriate if you suspect it is simply outdoor dust entering the area. The special cleaner is applied with a mop or an automatic scrubbing machine that you can rent from a home supply or tool rental store. The solutions are available at home supply and cleaning supply stores. Use the product as directed on the bottle to obtain the best results.