Mold & marble: What’s it all about?
There are six key ingredients mold requires in order to survive and grow.
Mold oh my! I can’t tell you how many calls I have received over the years from homeowners worried about mold. This concern usually happens after a flood. Should you be worried that marble, or any other stone for that matter, is prone to the growth of mold? Fortunately, in addition to being an expert on stone I am also a degreed biologist, so let me solve this concern. Let’s first look at what mold needs to grow. Mold in general needs six things to grow and thrive.
Without these, molds cannot develop:
Moisture- Being a living thing, mold needs moisture to thrive. To prevent mold, all you need to do is eliminate the water source. But what about a shower or wet area? Yes, this area can be prone to mold, but it is only one thing that mold requires. What if I have a flood or leak on my marble floor other than the wet area? Again, moisture can contribute to the problem, but it is not the only factor required for it to grow and thrive.
Tip: To prevent mold from growing in your shower, simply take a squeegee and remove the water from the walls after every use. You can also use towels to dry the floor.
Oxygen- Every living thing – mold included – needs oxygen to survive. If you remember your grammar school biology class, air contains 78% nitrogen and only 21% oxygen, so I guess we can say that mold needs air, not just oxygen. If air can’t get behind your marble floors or walls, then mold cannot grow. But don’t be fooled – air can find its way into the tiniest of spaces, so don’t assume your walls or floors are airtight.
Food- Mold also gets hungry and without a food source it cannot survive. So, what does mold eat? A nice cheeseburger perhaps. Mold is not a picky eater, and it can survive on almost anything organic, which can include the food we eat but also drywall, wood and other building materials that contain organic materials. Yes, even cheeseburgers.
Light- Mold hates the light, especially UV light. However, it loves the dark. Therefore, you will find mold in dark corners or areas where no light can shine. This is one of the reasons molds does not grow outdoors in direct sunlight. Sunlight has strong UV (ultra violet) light and will kill mold. As a matter of fact, UV lights are used by professional mold remediators to kill mold. So, you could put UV lights all through your house but only if you want a good tan. No, no, no – just kidding. UV light can cause skin cancer, so please don’t do that.
Temperature- Have you ever noticed that mold does not grow on your food in the freezer but does in the refrigerator? The reason is that mold needs a warm temperature to thrive. Anything over 32-degrees Fahrenheit and mold can grow, but the ideal temperature for most mold is above 60-degrees Fahrenheit or, for your metric people out there, 16-degrees centigrade. As the temperature rises, so does the mold growth. Summer can be a real mold producer since its not only warm, but there tends to be more mold spores in the air. More on this next.
Spores- Mold spores are everywhere. The air you are breathing right now contains mold spores. So don’t run for the mouthwash; it can’t be prevented unless you are breathing through a filter. So, why don’t these spores cause mold to grow everywhere? The answer is simply that it needs someplace to attach and to have all of its requirements met. Then and only then can mold take root and start to grow and thrive. Now, if you’re really grossed out you can always install an air purifier in your home, but this won’t eliminate 100% of the spores.
Marble and mold
To answer the question: Can marble contain or harbor mold? The simple answer is yes, if it has moisture, air, food, warmth and a dark place. In many cases, once the marble is dried and cleaned mold is not going to be a concern on marble or any other stone surface. However, if the proper environment is present, it can be a place for it to grow and thrive. This is rare, but not impossible, as most marble installations do not have enough of a food source for the mold to thrive. Without food or any of the other factors described above, mold will surely die.
Fred Hueston, aka, “Dr. Fred” has been a floor professional for over 40 years. To read more about him and his company visit StoneForensics.com.