5 Reasons Homes Are Invaded By Mold… and How To Stop It

Discover the 5 Mold Factors that let mold grow in our homes and the simple solution to stopping it in its tracks – without using harsh chemicals!

If you frequently have condensation on your windows, you most likely have a humidity problem. The term humidity simply means the amount of moisture in the air, and maintaining an ideal humidity level is vital to the health of your home and your family. The EPA reports that approximately 60% of all buildings in the USA have air quality issues of some sort, many of which are related to humidity and poor quality ventilation.

People are generally most comfortable when the humidity in a house is between 30% and 50%. Individual preferences will vary of course, but there can be problems if the humidity levels get too low or too high. If the humidity in your home drops below 30% you could experience dry or itchy skin, chapped lips, and breathing may start to become uncomfortable. If the humidity is consistently above 50% however, this can lead to some potential health issues. In addition to the air feeling heavy, there could also be a damp or musty smell.

This is usually caused by one thing:


You may experience this just as a musty smell throughout the home or just in a few areas, or actually see some visible spots in damp areas.

The most common places to check for these spots are:

  • Showers
  • Under Sinks
  • Windowsills
  • Walls near doors & windows
  • Exterior door frames
  • Entry hall carpet
  • Basement walls
  • Exterior walls

Mold growth is a serious concern for you and your family. Household mold growth has been linked to numerous health problems including difficulty breathing, sore throats, itchy eyes, headaches, worsening of asthma, and allergic reactions.

There are 4 commonly known requirements for the growth of mold in your home:

  • Available mold spores
  • Available mold food
  • Ideal mold growth temperature
  • Ideal mold growth humidity

If any of these aren’t present, mold won’t be able to grow. Let’s look at each of the requirements, and what you can do to control them.

Mold Spores

Mold spores are everywhere. Unless you live in an environment similar to a hospital operating room, there is already mold in your home. Mold spores come in each time you open a window or door, they are tracked in on your shoes or your pet’s feet, they settle on your clothes when you are outside. Without proper growth conditions, however, these mold spores are usually no more dangerous than common household dust so we can largely ignore this as a factor as they can be safely removed with a good quality air filter.

Mold Food

Mold eats organic matter. In homes, this is usually wood, drywall and carpet, which tend to be quite common in homes. Since we’re unlikely to replace our home materials with stainless steel or other materials that won’t support mold growth, we can also ignore this as a factor under our control. You can reduce the growth of mold on these types of surfaces by keeping them clean and free of dust. Regular cleaning will also work to remove any mold spores that do settle, before they can have a chance to start growing.


Mold will grow in a fairly wide temperature range, unfortunately, it’s also the same range that we enjoy living in, which is commonly referred to as room temperature. As long as the room temperature is relatively comfortable for us, it will also be very comfortable for mold. Since we’re unlikely to want to live in an uncomfortable temperature just to inconvenience the mold, we can also ignore this as a factor we can (or are willing to) control.


This brings us back to humidity. Unlike the other 3 common factors, this is something we can exert a considerable amount of control over. The technology to regulate humidity is very common and accessible, and in fact, dehumidification is a core function of every household air conditioning system. This is one of the reasons mold is less common in summer months in homes that have air conditioning. Reducing the humidity levels to below what the mold requires to grow effectively stops it in its tracks. Without enough moisture, it is much harder for it to grow and spread.

If the humidity in your home is too high, and you don’t have an air conditioner (or it’s too cold to use one) the best way to lower it is with a dehumidifier. Even if you don’t have a mold problem, a dehumidifier can help make your home more comfortable. Always remembering to use a ventilation fan during & after cooking or showering will help as well, to avoid any excess moisture in the air during colder times of the year.

The 5th Factor

There is actually a 5th contributing factor that many people are just learning about. Just like our digestive systems are teeming with microorganisms, so are our homes, in a complex ecosystem called a microbiome. Mold is part of this household microbiome, and we can influence it as well.

A generation ago, we were routinely exposed to a wide range of beneficial bacteria from the environment. We were exposed to these environmental bacteria when we played outside as children, when we walked through the grass, or when we played with the family dog. Over time, these beneficial bacteria spread to surfaces in our homes where they acted a bit like an immune system for the house.

These environmental bacteria are utterly harmless to us, in fact they are found in common things like yogurt or drugstore probiotic supplements. But, they act like loyal guard dogs and help protect your home when they encounter something harmful like mold spores.

Unfortunately, the indiscriminate “war on germs” of the past generation has effectively wiped out these beneficial species from our homes; casualties of “friendly fire” as we attempted to eliminate the few bad species with our dizzying array of anti-bacterial soaps, cleaners, wipes, etc.

Without these natural helpers around anymore, we’ve accidentally left our homes vulnerable to colonization by mold when the conditions are suitable.

You don’t need to start shoveling dirt into your home to bring these healthy bacteria back however, there is something MUCH easier you can do. Just as you can help restore the beneficial bacteria in your gut by taking a probiotic supplement, you can help restore these beneficial bacteria to your home with an environmental probiotic in the form of a probiotic spray like Homebiotic.

Homebiotic helps restore your home’s natural immune system, adding an extra line of defense against mold, germs, and bad odors before they become a health issue.

Homebiotic is:

  • Simple and easy to use
  • 100% safe to use around children and pets
  • Clinically proven to ASTM standards to inhibit mold growth
  • Formulated with naturally-occurring non-GMO environmental bacteria which have years of study backing their safety and effectiveness against mold growth
  • natural way to help make your home healthier
  • An effective addition to your healthy cleaning routine

Homebiotic can be applied in just a few seconds, wherever and whenever needed. It’s ready to use, so you can spray under your sinks, around doors and windows, in your vehicle, and anywhere you want an extra line of defense against mold.

I love this stuff! Thanks Dave Asprey for the recommendation! In MN the winters are horrible with no humidity outside. Our windows unavoidably get wet at the bottom of the frame as we use a whole house humidifier. I usually clean the windows with vinegar often, but it always comes back. I just thought there wasn’t a solution. After using Homebiotic the mold did not return. What a great product! Thank you!

Joseph Torbert

Homebiotic Customer

Get Homebiotic and start defending your home today.