Causes of mold growth in home

Mold is a type of unwanted fungi that can be black, brown, yellow, pink, and smelly. They are found both indoor and outdoor. Molds develop in moisture and can be hidden behind drywall, attics, carpet, roof, damp basements.

Molds need conditions like a food source (wood, drywall, cotton), darkness, warmth, oxygen, moisture. Unfortunately, they can also lead to some serious health issues such as bronchitis, respiratory infections, respiratory allergies, asthma, pulmonary hemorrhage (bleeding in the lungs), etc.

mold growth in home

Some major reasons which help mold to grow are


If the weather is humid and it rains for several days, you will notice mold starts to grow in your house, and it can be a recurring problem in your house. If your home is not ventilated, then humidity stays high for a long time. The HVAC systems in the house also create humidity problem when it artificially cools or heats the air.

Mold spores

Mold is a microorganism that is prolific and cannot be seen from your naked eyes. They usually enter your house from outside. Air movement helps the mold is spreading. Once these mold spores enter your home, it becomes impossible to remove them. The only places where they do not occur are deserts and ice land.


Mold needs food to survive and reproduce. Molds eat the surface, wood, etc. if you find mold in your bathroom, they feed on organic materials like wood panels or wallboard. They can also feed on a minuscule amount of dust and dirt. They can also feed themselves in your attic, wall, gypsum sheetrock. Molds can eat clothes, luggage, damp cardboards, newspapers, fabrics, etc. Air can also contribute to their diet.

Oxygen supply

Mold cannot live without oxygen as they need air to grow and reproduce. Air does not only help mold to grow but also helps in their movement from one tight corner of the house to the entire house. Molds do not require a large amount of air, but the air which is present inside the wall cavities can easily assist mold colonies to grow.

Lack of sunlight

Mold can die in direct sunlight. The UV rays are the only natural substance to kill mold as sunlight kills mold cellular structure. Mold prefers limited light or complete darkness. Artificial light is different from sunlight and is not able to destroy its structure. It is not possible to bathe your house completely with sunlight, but you can find things that can emulate the sun’s wavelength and help you destroy mold.


Mold cannot tolerate too cold or too hot conditions. They grow at normal temperatures. The freezing temperature will destroy them, and burning will destruct their structure and prevent them from growing. Temperature levels inside homes are very appropriate for molds to grow and culture their lives. Humid conditions allow molds to colonization.

The causes of mold growth are quite clear, and preventing them in your house depends on identifying their prime place and destroying it. Educate yourself about the signs and symptoms and take the best preventive measure.