I didn't know much about mold until I had the joy of being a property manager for an apartment complex. Looking back it was one of my top five jobs which had taught a great deal about cleaning mold.
Wallpaper can hid the mold. While remolding a bathroom, I was shocked to find a large mold problem that was hidden by the wallpaper. Even worse if the old attendants complain about now feeling well, the mold could have be part of the problem.
Now when I move, its top on my list to remove or replace any wallpaper.
More then you want to know but mold can be under the carpet as well. One apartment was so bad that the entire crew got sick even wearing face mask because of the mold caused by someone who had accidents on the carpet and didn't clean it.
Even after mold is killed it can leave a nice stain behind. Just covering the stain with paint, may not cover the stain. Now I highly recommend Kilz brand paint or a paint that says it is designed to cover mold stains. Anything else the mold stain will just pop through. I always used the Kilz brand paint because they also say they help to prevent mold from growing back.
Mold can affect everyone and even be deadly. If you not sure what kind of mold or how to handle the mold, you should call a professional to asses before cleaning. Mold spores can spread through your home and make everyone very sick.
A good way to kill mold is one part bleach to three parts water. It is a good idea to see what kind of mold before cleaning, as suggested above.
There is a lot to learn about mold. However you should always wear a mask when cleaning mold.
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