My basement tenants used to take hot showers and keep all the doors closed preventing the humidity from reaching the return duct and causing excess humidity/condensation. I installed a bath fan, but in the meantime some mold developed in one of the corners - on the painted drywall just above the baseboard. I've read different opinions on how to handle the mold. One says cut out that area of drywall (which I'd like to avoid), using bleach or boric acid. Advice?
I consider all molds to be toxic mold unless I have it lab tested. If you do not use the proper protection and follow remediation protocol, you run the risk of infecting yourself and other areas of your home with mold. Using bleach will not work on some molds and due to the ionic structure of bleach; it is too large to penetrate any porous surfaces to kill the root system of mold. Chlorine and chlorine based products should only be use on non-porous surfaces such as tile. Bleach and Boric acid are irritants to skin and to the respiratory system. I am amazed that bleach is allowed to be sold to consumers, it's very caustic. You may have mold in other places. I recommend an inspection and a lab test to determine what type/s of mold is present. Your rental property is an investment, protect your investment with professional help.