Does Bleach Kill Mold?
Mold is a persistent problem in damp, humid environments, prompting many to turn to bleach as a solution. Bleach, a powerful disinfectant containing sodium hypochlorite, is widely believed to kill mold effectively. However, its efficacy depends on the context and surface type, making it a topic worth exploring.
NOTE: The main reason that people think that bleach will kill Mold is that Bleach has such a strong smell. People assume that it will kill anything. That’s mostly untrue.
Bleach can indeed kill mild if the mold is submerged in the bleach for a prolonged amount of time. Its active ingredient disrupts fungal cell structures, effectively eliminating surface mold and preventing regrowth when applied correctly. Studies, such as those from the Environmental Protection Agency (EPA), support bleach’s ability to disinfect hard surfaces, provided it’s diluted properly—typically one cup of bleach per gallon of water—and left for several minutes before rinsing.
However, bleach falls short on porous materials like wood, drywall, or fabric. Mold penetrates these surfaces with root-like hyphae, and while bleach may whiten or kill surface spores, it doesn’t reach deeper growth. The water content in bleach solutions can even exacerbate mold by adding moisture, encouraging regrowth. Experts from the Institute of Inspection, Cleaning and Restoration Certification (IICRC) recommend alternatives like commercial fungicides for porous surfaces, as they penetrate better without feeding the problem.
Moreover, bleach poses health risks—fumes can irritate lungs and eyes—necessitating ventilation and caution. For comprehensive mold remediation, consult a Professional Mold Removal Contractor to get a proper understanding of how to REMOVE mold.
NOTE: Killing mold should not even be considered as a final solution to getting rid of mold growth in a home. The human respiratory system reacts the same way to dead mold as it does to live mold. REMOVING THE MOLD should always be considered the best plan.
Drafted by Randy Schmidt, President, Madison Property Restoration