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Can mold grow on brick and hardwood floors?

Q. Hi, I recently moved into an old building in eastern TN built around 1890. Since moving in, my asthma has flared significantly, and is worse when I spend a few hours or more in the building. I have been tested positive for moldallergy, however I cannot find any mold. The building was renovated 4 years ago and everything, except the brick walls (now exposed), and hardwood floors and beams were replaced. I haven’t been able to find any mold. Can it grow on brick? If so, what should I look for? How about hardwood floors? There are no apparent water leaks. Thank you very Much.

A. Hi Eastern TN, It sounds like you may have a humidity problem. Yes mold needs Water, Heat and a food source but the water does not have to be in the form of running water as like a burst pipe. High humidity, above 60%, will be sufficient to allow Mold to grow. Mold can grow on any organic material. We all have dust around the house and most of the dust we find in homes is organic. This dust settles on everything thus making it possible for Mold to grow on all surfaces. Remember stop the water stop the Mold.

Mold Question answered by Jim Thomas of Jim is a Master Carpenter and C.I.E. (Certified Indoor Environmentalist) with 35+ years of experience in the restoration industrial including a specialization in mold remediation.

Can mold grow on plastic and, if so, is there a way to clean it?

Question: We recently bought a used plastic outdoor toy set for our children. We had planned to clean it up and put it inside in our basement. While we were able to disinfect and clean the outside of the toy with a detergent, I am concerned that there may be mold inside the toy in areas I can not reach or scrub. When held to light we can see “spots” through the plastic. We cannot tell if it is mold or dirt. Can mold grow on plastic like this and is there a way to clean it? If not should we not bring it inside our home and just leave it as an outdoor toy? Thank you for your help!

Answer: Mold can definitely grow on plastic. If there is moisture and humidity and a way for the spores to gain access, mold start to grow. Cleaning will depend on the type of toy and your ability to access and disinfect the area. If you are unable to thoroughly remove the potential mold growth then, being better safe and sorry, I would suggest you clean it as best you can and leave it as an outside toy.

Thanks for stopping by! Feel free to leave a comment if you have any further questions.

Jonathan Wold

Can outdoor hot tubs and jacuzzi’s grow mold?


I’m wondering if HOT tubs or Jacuzzi’s outdoors can fester with mold underneath a deck or foundation…? I smell a musty smell even tho it’s outside… Thanks.


In our experience, any environment where humidity is present and moisture can sneak in will lend itself to mold growth. The heat generated from the unit can cause condensation which, in your case, may be leading to mold growth under the deck or foundation.

Jonathan Wold

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