What is mold?

Mold is a microorganism that is classified as fungi. It’s a living organism that doesn’t fall under either the plant or animal classification in accordance with scientific standards.

There are many different types of molds that can be found in the environment. Invisible to the naked eye, mold spores travel through the air and are commonly found in soil and on decaying matter.  Outdoors, mold plays a big part in the natural degradation of plant matter. However, when mold travels indoors, it can be hazardous to your health.

Mold comes in a variety of colors including white, brown, orange, green and black. Mold often has a furry look or resembles a stringy slime, but certain molds can also have a powdery-look. Black mold is considered to be the most dangerous type of mold found in homes. Finding black mold in your home is scary and should be addressed immediately to avoid potential adverse reactions to the mold.

Mold can grow at an extremely fast pace. A mold colony can form in as little as 48 hours from the initial contact a mold spore makes with a surface.

Health Risks Caused by Mold

Mold exposure can lead to several health-related problems. With its natural ability to travel through the air, the inhalation of mold spores can create a variety of respiratory ailments. Common side effects include asthma, allergies, respiratory infections, sinus infections and skin rashes. Mold in air ducts can cause allergic reactions. In some cases, mold exposure can even be fatal.

Toxic black mold covers a basement wall. (Photo by Gilbert Boucher)

How does mold grow?

As with all living organisms, mold requires specific elements to develop, grow and thrive throughout the environment. These elements include mold spores, moisture, proper temperatures and carbon atoms which are used by molds as a feeding agent. When these elements are plentiful in a given location, it creates the perfect environment for mold growth. To avoid mold growth and mold symptoms in your home, consider these elements.

Mold Spores

Mold spores are invisible to the naked eye. They are carried through the air and have the ability to attach to almost any solid object. Mold spores especially like to attach to porous items or damp surfaces.


Mold doesn’t have an allegiance to one specific climate. It prefers temperatures similar to the human body and can grow in both hot and cold areas. Humid and moist areas are the most prone to mold growth.


Moisture is created for a magnitude of reasons and molds will seek it out. From weather and climate conditions to leaky pipes found within the home, complete moisture control is impossible. Areas that trap condensation or water vapor are ideal locations for mold to grow. This can include spaces such as under tarps, in cabinets and behind furniture.

Feeding Agent

Most living things release carbon atoms that mold will use as a food source. If the first three requirements for mold growth are met, it will use almost any carbon-containing organism as a food source. Everything from skin cells to wood can supply mold with the necessary nutrients for growth.

Preventing mold growth

Even the cleanest homes have the potential for mold. Residential building structures have many areas that offer prime environments for mold to grow. Basements, bathrooms, utility rooms, laundry equipment and kitchens are some of the areas where black mold is often found. Homeowners can take proactive steps to drastically limit mold grown, but unfortunately, it’s literally impossible to eradicate all together. 

Tips for preventing mold growth:


Basements especially should have a ventilation system in place. This can help to bring fresh air in and push water vapor out. Homes that are not equipped with windows should use a dehumidifier or circulation fan.  

Fix foundation cracks

The smallest crack or leak can provide a perfect habitat for mold growth. Window frames, doors and corner locations of the foundation can be sealed using a water proof chalk. This is a service that should be performed at the beginning of rainy seasons.

Keep stored items organized

When storing personal belongings or furniture, it is best not to pile items on top of each other. This can cause moisture to get trapped, and it prevents air circulation.

Try baking soda

Baking Soda helps to absorb moisture. By placing a box of baking soda under kitchen and bathroom cabinets and in the refrigerator, it will prevent moisture from forming and creating an ideal habitat for mold growth.

Keep HVAC systems free of mold

Air ducts, heating systems, air conditioning systems and filters should all be cleaned and changed regularly. This will prevent mold from growing and spreading throughout the home. Mold growth in air ducts and HVAC systems allows smells and mold spores to travel quickly throughout a home. Seek the help of a professional HVAC technician or air duct cleaner if you suspect mold or notice mold symptoms in these areas.


Video: Mold Removal

Mold testing and removal

Testing for mold

There are several home mold testing kits on the market. However, experts stress these kits should only be the first step. The testing kits usually come with a swab that can collect a small sample of mold. Some kits are designed to collect and grow mold in an incubator while others will instruct the user to send the sample in for lab testing. Home mold test can be misleading because they do not give an indication of the amount of mold present or how dangerous it is.

Hiring a professional for mold testing and removal

Professional mold removal contractors are individuals that are licensed and professionally trained in proper mold identification and removal techniques. These mold removal contractors use industrial equipment and cleaning supplies to kill and remove mold and mold colonies from the home.

During a mold inspection, a technician will perform a visual inspection and then test the air with a device referred to as a “sniffer.” Depending on the findings, the technician may send a mold sample in for lab testing.

Leave a Comment - 14



Subject: Mold and mold spores as well as water damage

Experienced water damage to window frame several months ago and now have visible mold spores throughout the house It has destroyed my mattress,cushions on sofa and continuing to destroy all my belongings as well as my health and the health of my pets.


Subject: black mold

Over three years ago my neighbor went into a nursing home. Her condo, one floor next to mine, remained empty. Last week the entire condo was gutted with hazemat professionals due to black mold.
I am concerned about my condo because my master bedroom, bathroom, kitchen, dining and part of living room are against her wall. I believe we have firewalls but is that enough!!
Please advise.


Subject: mold

Hi, I had our duct vents cleaned and was informed of mold in the main unit. I was quoted a price of $921 to clean/remove. Is this reasonable in your opinion?


Subject: mold

We all try to get somewhere with the landlord to no avail. Dr. Don't want to help sick been to Dr x2 as well as 2 emergency rooms .everyone thinks you will sue so they won'teven face it. Inhaler and cough is the paperwork .they aactually won't even put that I am complaining about being sick from mold in my home.

H. Helen

Subject: mold in my condo

I have had mold smells from leak in roof. Roofer fixed leaks supposely but I opened the ceiling there is black mold in there and HOA broad and property management refused to fix it. The bylaws state this is there responsible for it and if I fix it I will be in legal trouble. I dont know who to contact for help. Any suggestions.


Subject: Chlorine dioxide better than chlorine

Anyone needing to kill microbes including mold should research chlorine dioxide.


Subject: moldy smell

last summer we had an inordinate amount of rain (no leaks thankfully) and i failed to change my HVAC filter in a timely fashion (it was very dirty with a small amount of black on one edge). when i am in my house nothing seems to smell however when i am out (work, friends etc) everything i wear smells moldy. i have had the HVAC system checked with nothing apparent discovered. I have lived in this house for 8 years with no prior problems. How can i get this smell out?


Subject: Older 1906 home in Pacific Northwest

Have renovated kitchen and all bathrooms still doing hardwood floors, live on slope basement is 1100 sq. ft. Cement brick and granite walls. Rains always has water in basement only about a 8 ft by 40 ft area, about 6 months out of year.Steps leading down to basement concrete cement, basement does have 5 windows and fireplace, I do see mold on tile, if this is removed because water is always in basement how to prevent from coming back, also baseboard on first floor in not installed so the air from the basement is coming up, should I have that installed? Thank-you


Subject: sick sick sick

Hello.. I moved into a condo that had roof leak in a bedroom. It was a heavy leak. As a substancial amount. Of wayer came out of 3 spots over a period of 2 years. Roof was fixed, however not from inside.cosmetically it wasn't pretty, but noticable. Over 5.years I have developed extreme cognitive illnesses and joint pain and tumors. My question.... if this leak was stopped, and being in New Mexico (dry) what are the chances of mold surviving in such a dry climate? Is candida considered part of the mold testing like black mold?


Subject: Black mold brown mold green

Black mold brown mold green mold, it doesn't matter what the color. Black is no worse than the others. The harm comes in those that produce toxic compounds, which can be any color of mold. Don't get scared by terminology. Mold just needs moisture plain and simple, light or dark, hot or cold, it will grow in the areas with moisture present. If you can identify the source of moisture and stop that, you cut off the cause of your mold.


Subject: hoping to prevent mold

A week ago my ceiling leaked, with lots of water on my carpet; I just sprayed some vinegar where this happened, hoping to prevent any mold; hopefully, it will work. My front door to my apt though has been stuck for a week, cause of swelling up from the water; hopefully no mold under it when (months from now?) I do finally open the door.

Frank Kelley

Subject: Mold

Nothing works better than BLEACH - Period. Vinegar and water? NO WAY! You try two spots side by side with bleach and vinegar - You can actually SEE Bleach KILL all the mold as it turns to white after a few seconds and kills all mold Fast. I have use bleach for many years and I know it works.


Subject: Black Mold

I live in an apartment complex. I first noticed black mold in ad around the toilet water flow. It is extremely hard to remove. I used bleach tablets in the tank and that removed the mold but I must keep using the tablets or the mold grows back. I took off the strainers to the faucets -- black mold growing inside the faucets where the water comes out. I try to clean the faucets with a bleach filled small bowl held up to the faucet, but it is a hard way to try getting rid of the mold. I have talked to apartment management and they tell me to use bleach and there is no way it can grow in the faucet water flow.

Any ideas who I can contact to have this problem taken care of? I filter any water I drink. Thank you.
Jeanne Kinn

Blas Perez

Subject: Mold

A well ventilated area and well lit. That's it to avoid mold. If lighting is difficult,a dehumidifier works great.

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