Which Zinsser is best for mold?

Which Zinsser is best for mold is Zinsser Mold Killing Primer, which is specifically formulated for mold and mildew, though other Zinsser primers also help with mold stains. Zinsser offers Zinsser Mold Killing Primer, which is an EPA-registered product that contains a fungicide to kill existing mold, mildew, and other fungal organisms on contact and prevents future growth on the primer film, making it best for areas with mold issues. It is water-based, low odor, and can be used on interior surfaces like drywall, wood, and concrete after cleaning mold. For blocking mold stains that remain after cleaning, Zinsser Bulls Eye 1-2-3 Water-Based Primer with mold resistance is good for preventing mold growth on primer film in high humidity areas like bathrooms and basements. For severe mold stain blocking, Zinsser BIN shellac-based primer is excellent at sealing in residual mold stains and odors that remain after cleaning, though it does not kill mold itself. Best practice per EPA is to first remove mold physically using detergent and water or bleach solution, fix moisture source such as leaking gutters, plumbing leaks, or poor ventilation, allow surface to dry completely, then apply Zinsser Mold Killing Primer, followed by mold-resistant topcoat paint. Do not paint over active mold without cleaning, as paint will not stop growth. Zinsser Mold Killing Primer costs about 30 to 40 dollars per gallon.