We've been asked to remove a thin epoxy coating from a 20,000-square-foot warehouse floor. What methods can we use to remove the coating?
Treating the floor with a chlorinated solvent (paint stripper) is an effective way to remove the coating without damaging the underlying concrete. Because chlorinated solvents are hazardous substances, they must be used with caution. Since the stripped coating will be a hazardous waste, you'll have to obtain a hazardous waste generation license, place the coating in labeled drums, and transport and properly dispose of the drums. After the floor is stripped, you must wash and neutralize it. Removing the coating with a paint stripper will not damage the floor surface, but if the existing coating is pigmented, it may leave a colored stain within concrete surface. A second method to remove the coating is to shotblast the floor. However, shotblasting will take off the top surface layer of concrete along with the coating, leaving a roughened surface. This may be unacceptable if the owner does not plan to install a new coating to restore a smooth floor surface. Another method is to use a recently introduced floor preparation machine that uses a belt sander and free flint abrasive to remove coatings. In addition to taking off the coating, this machine will abrade the concrete surface, but it will leave a smoother finish than a shotblaster.