Mold needs something organic, like dirt, leather, cardboard, or food in order to grow. It takes a lot of moisture for some types of
mold to grow where others need very little. There are tens of thousands of molds that have been discovered. Not all of them are toxic but some can produce lethal allergic reactions in people who have weakened immune systems or have other compromising health factors. Some molds are just plain molds. There are mold spores in the air we breathe and mold in some of the foods we eat. Mold is a part of life as we know it but at the same time mold on your brick surfaces can be very unsettling and unsightly.
Removing mold is not difficult. Safety is key; you will want to wear goggles that do not allow air in for ventilation and rubber gloves to prevent the mold from getting on your skin. Black mold, dark green mold, and virtually every other type of mold is able to grow on brick surfaces. Brick patios, which will
have a thin layer of dirt on them even if it cannot be seen, are especially prone to mold growth. The mold is not actually growing on the brick but on the dirt. If there is moisture that sits on a particular part of your home, especially after rain, you may get mold growing on the actual brick on your home.
One cleaner I recommend for cleaning brick in general whether you have dirt stains, rust, mold, or mildew is the ChimneyRx Safer Brick and Masonry Cleaner. Muriatic acid was once recommended for cleaning brick but that can bleach the brick and stain it in other ways. If you would prefer you can go to your local Home Depot or garden store and get a weed killer. You’ll want to saturate the mold and let it sit for a period of time to allow the formula to work. Scrub the area with stiff bristle brush and rinse. You may have to repeat this process many times especially if the mold is very developed. Be cautious by not getting any chemicals on your skin or in your eyes.
If you have more than ten square feet of area covered in mold you may want to consider bringing in a professional who will be able to assess why the mold is growing there and help you prevent it from coming back. If you have mold growing inside your home, especially in your bathroom you want to take care of that as quickly as possible for health reasons.