Removing concrete sealers can be a difficult task when done improperly or without the right materials. This process of replacing old, damaged, or failing sealers from concrete is many times necessary when restoring old or damaged surface substrates.
Methods
The two most common ways to remove concrete sealers are by using chemicals or machinery to remove the coating. Using machinery consists of sanding or blasting your surface to the point where the old sealer has been removed. If not done correctly, this method can result in damaging your surface to a point where new sealers cannot be applied. Dust and noise are also a side-effect of this method and should always be considered prior to execution.
In most cases, using a chemical stripper is the easiest and most cost effective way to remove an old sealer from concrete. Chemical strippers are made from alkaline chemicals that dissolves and deconstructs the sealer film, allowing for easy removal from your surface.
Chemical Removal Procedure
For best results, apply at a temperature between 65-85 degrees Fahrenheit. Very slow stripping action will occur at 55 degrees. Shake can before use. OPEN SLOWLY and allow air to escape. Apply a generous coat of stripper with an inexpensive brush, irrigation type airless sprayer with a vitron or teflon “O” ring. Brush or spray in one direction only. The stripper will react on most surfaces in 10-20 minutes depending on climatic conditions.
Remove residue with a putty knife or wipe clean with a dry cloth. Place residue in a metal container for proper disposal. If any residue or finish remains, apply a second coat and allow 2-10 minutes. Scrub with a coarse steel wool pad, moistened with water or paint thinner. When all residue is removed, wipe your surface with a clean moistened cloth with lacquer/paint thinner.