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Temperature and Mold

At What Temperature Does Mold Grow?

There is a common misconception that mold only grows during the warm summer months, but this isn’t the case. The temperature does have a dramatic effect on the way mold grows, but it isn’t just a seasonal problem. Mold can grow all year if the conditions are right. Mold is smelly, unsightly, and hazardous to your health. Knowing where to look during the different seasons of the year can help you eliminate the threat of mold before it leads to disaster.

In this post, we’ll discuss the relationship of climate, temperature and mold.

A General Overview of Mold Growth And Temperature

Mold needs oxygen and water to grow, but it also requires a food source and compatible temperature to really thrive. Even when ideal conditions aren’t available, it’s possible for mold spores to go into a dormant resting state until things change in their favor.

At What Temperature Does Mold Grow?

Generally speaking, mold can’t grow if the temperature dips below forty degrees Fahrenheit. For this reason, many refrigerator settings are set at thirty-nine degrees. An ideal temperature for mold growth is between seventy-seven to eighty-six degrees Fahrenheit, especially when there is a lot of humidity in the air. Temperatures have to rise above one hundred degrees or below freezing to effectively kill mold spores.

temperatures and mold

Food Sources

Mold also needs the right food source to grow well and will grow on materials or in places where it can digest organic matter. This makes it difficult to remove mold from an environment, as there is pet dander, dust, dead skin cells, and other airborne particles all throughout a house that can feed a colony of mold. It does require water and oxygen, though it only needs a low concentration of oxygen to stay alive. These necessities often lead to discoveries of mold in basements, attics, cabinets under sinks, HVAC ductwork, or in a bathroom.

Health Effects 

Mold can do serious damage to your home, either from ruining your carpet, causing drywall to bubble and determinate, creating stains on ceiling tiles, or infesting ductwork. Long-term exposure to mold spores can also cause health problems. People typically display respiratory conditions when exposed to mold spores with symptoms that include asthma, wheezing, coughing, and fatigue. Symptoms of toxic ingestion can also be persistent headaches, runny nose, watering eyes, and rashes. The impact mold has on your health makes it a priority to address it, no matter what season you are in. Fortunately, Mold Remediation’s 24/7 hotline connects you with certified, licensed, bonded and insured mold remediation companies in your immediate area.

mold remediation companies

Winter Months and Mold Growth

So long as there is enough moisture in the air, a plenteous food source, and the right temperature, mold can still grow during the winter months. There are different types of mold, and depending on which mold species is growing, it could be more suited for cold temperature growth. Though there are minimum requirements for many fungi varieties, these comfortable conditions often correspond to the temperatures the average home maintains throughout the year. If your thermostat is setting between 60 and 80 degrees Fahrenheit, you are creating a climate where mold can thrive.

cold temperatures and mold

Not all parts of the United States experience freezing temperatures throughout the winter. This makes it difficult to truly kill mold spores. The extreme variations in the winter cold, especially when dropping below 32 degrees Fahrenheit, are damaging, but the spores may not die and can wait for the house to warm up or the warmer months to arrive to come out of hibernation. Temperature alone isn’t enough to tackle a problem with mold. You also need to treat the source of mold and employ preventive measures.

Increasing Moisture

During the fall and into the winter, there is an increase in dew and precipitation, creating films of water on different surfaces around a house. Many find that window panes are a key gathering spot for moisture, creating an opportunity for mold to grow and expand. Windows collect a lot of condensation during the winter months, as the heated air inside the home makes contact with the cold glass being chilled from the outside. Water vapor is deposited on surfaces where this clash occurs. This is why mold can be seen more readily along the frames of windows or on the sill.

Persistent Allergy Symptoms 

allergies to mold

Because people spend more time indoors when the weather is cold, you may notice that your allergy symptoms increase during the wintertime. This can potentially lead you to discover a problem with the air quality in your home. Running your heat may disperse the spores throughout other areas of the home, making it harder to get away from the problem.

mold growth temperature

Summer Months and Mold Growth

The temperature during the summer months generally accelerates the growth of the mold. Not only is the air warmer, but more frequent rain and higher humidity increase the likelihood of colony growth. Few locations across the United States see heat temperatures that exceed the minimum requirement to stifle and kill growth, leaving many exposed to the potential infestation.

hot temperatures and mold

Ventilation Issues and Moisture Buildup 

If your home has poor ventilation, you may have an increase in humidity and a need to get rid of mold in your ducts. A free flow of air is needed to properly circulate vapors, and stifling that flow can lead to condensation building up on the windowsills, basement windows, or other areas where the colder internal air clashes with the heat from the exterior. Many times, an HVAC unit will extract a certain amount of water from the air, but if the unit is older and doesn’t route the water to a free-flowing drain, there is a greater likelihood of leaks or overflowing drip pans. The presence of moisture creates an opportunity for mold.

The Spread of Mold Growth 

Summer is the perfect temperature for mold growth, but the breezes and winds that come through are also ideal for carrying mold spores around the house. Mold will thrive on soggy carpet or cardboard, inside ductwork, on insulation, or the wooden support structures of your home. It grows and multiplies quickly, putting your health and home in danger if left unaddressed. Wherever you have dark places in your home, you need to be more vigilant in checking for the presence of mold. You may end up smelling the musty odor before you see visible signs of growth, but you can be on the lookout for signs of a water leak or water damage.

Roofs and Exterior Mold Growth 

roof with mold growth

You would be surprised at all the places mold can grow during the summer. Not only could a windstorm blow off roofing tiles or cause a limb to puncture through the roof and let in rainwater, but a build-up of debris and leaves in the gutter system can cause rainwater to back up and flood onto the roof. This excess water can force its way in through the seals and cracks along the roofline, dripping water into the attic. However, the same debris and dead leaves in the gutter can also breed mold underneath, and the spores can be swept through the air and land on other places to start new colonies.

Mold Growth in Small and Dark Areas 

Watch for signs of growth in crawl spaces under the house or in your basement, especially during rainy periods. Water and moisture can get trapped in these dark areas and breed mold quickly. You may notice the musty odor when walking around the house or coming up from under the floor vents. Small animals or rodents that get under the house can also tear holes in ductwork, leaving it exposed to additional moisture. Thoroughly clean around your HVAC unit to prevent debris from building up and decaying around the system. This reduces the possibility of mold spores getting caught in the circulation and forced throughout your home.

Year Round Mold Remediation

Mold should be address immediately upon suspicion of its growth. Growth occurs rapidly when the conditions are right, so whether rain, snow, sleet, hail, or blistering sun, you need a game plan to address mold. Contact MoldRemediation.io to ensure that your problems are addressed appropriately, and so that serious damage and health concerns are avoided.

what temp kills mold

Mold Inspections

Hiring a professional mold inspector will give you peace of mind. Being in a position where you are uncertain as to the toxicity of mold in your residence can be extremely stressful.

At moldremediation.io, we pride ourselves on being quick, thorough and effective in how we communicate the mold remediation tests that we perform for our homeowner clients.

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