What is mold?
Mold is a type of microorganism in the kingdom of fungi, meaning they are from the same family as things like mushrooms and yeast. Globally, over 100,000 mold species have been discovered, and there are over 1,000 common types of mold in the United States.
A mold spore is 10 microns long (or 0.0002 inches), making it invisible to the naked eye. Because of the size of a mold spore, it’s almost impossible to stop it from entering your home. Instead, the focus should be on making mold as unwelcome as possible when it does enter.
Mold has a set of specific conditions in which it flourishes and develops. Most of the fight against mold involves preventing the conditions that mold enjoys.
If you do have mold, the cost of removal can mount up, particularly if left unchecked. On average, you will pay $15 – $31 per square foot for mold removal, with a national average of $2,325. Since you’re effectively paying by the square foot, you have a strong vested interest in addressing the problem quickly.
This guide is designed to tell you everything you need to know about mold as it pertains to your home, from how it gets in, to how to get it out.
As mentioned above, there are over 100,000 different types of mold, many of which have not been classified. Molds can have a variety of different appearances, colors, and textures.
However, the most common types of mold that grow in your home are the following four:
This type of mold is typically found in damp places, such as in showers or under sinks.
This can exist in either cool or warm areas and prefers to grow on either fabrics or wood.
This is a blue/green mold that flourishes on materials that are water damaged.
However, if the mold in your home doesn’t follow any of the above phenotypes, there’s no reason to panic (or conversely, to assume it’s not mold). Because of the breadth of different types of mold, you should work on the basis that any type of mold growing in your home needs to be removed.
HOW DOES MOLD GET INTO A HOME?
The first point to make here is that it is not possible to prevent mold spores from entering your home. Of course, you could hermetically seal your home and spray everyone (and everything) entering with a disinfectant spray, but this still would not prevent mold spores from getting in. However, that doesn’t mean that you shouldn’t do anything to check its spread once it does make an appearance.
Here are the most common ways mold enters a home:
Through the Air
The most common way that mold gets into your home is through the air. Mold spores can be carried in the wind, meaning that they can get in through:
On People or Pets
Mold spores can also be carried into your home via clothing or pet fur. Dogs or cats, in particular, are major sources of mold because they tend to like exploring strong-smelling areas in the undergrowth – places where mold is prevalent.
Fur also acts as an excellent way of storing mold spores. People also commonly track it indoors on the bottoms of their shoes, as well as on their clothing.
WHERE DOES MOLD GROW?
Once mold spores enter your home, mold can quickly flourish. Mold requires relatively little help to grow, requiring only warmth and moisture to thrive.
As a result, the most common places where mold flourishes are:
As the next section will show, once mold has found a base in your home, it can very quickly spread, resulting in an extremely unpleasant and expensive experience.
Once mold spores are in your home and have found a humid, wet place to take hold, they will begin to spread. Depending on the type of mold you have, you may notice green spots appearing on your wall or tile; these will start to spread across the surface. Before too long, however, mold will begin to spread.
KEY ELEMENTS OF GROWTH
Mold needs three things in order to grow:
This can come either directly from a water source (i.e. a leak or a flood), from humidity in the air, or sometimes even from a food source.
Mold spores can ‘feed’ off almost every type of material, from leather and wood to porous materials such as beds and couches.
The optimum temperature for mold spores is between 32 and 120 degrees Fahrenheit (a range far greater than humans regularly endure). However, mold flourishes best in temperatures between 70 and 90 degrees F. If you freeze mold below 32 degrees, it doesn’t die, it just remains dormant, and can ‘come back to life’ when the temperature rises.
THE STACK EFFECT
The stack effect is where warm air rises throughout your home and ultimately exits through the roof. Because of this, mold can very easily spread to all parts of your house.
Unfortunately, the most prevalent place for mold to enter a home is via the basement; the stack effect will, therefore, draw mold spores up from the lowest floor all the way to the top of your home.
HOW LONG DOES IT TAKE?
A mold infestation can, from the spores entering your home, take as little as one day to take hold. However, the range is usually between 1 and 14 days.
PROBLEMS CAUSED BY
As well as being unsightly, mold can cause some real problems within your home. The most important of these is to the health of those who come into contact with it.
Mold particularly affects the respiratory tract, irritating the lungs and the throat. For those who have a weak respiratory system, mold can compound an existing condition. As a result, the most common health problems of those who inhale mold are:
Research by the World Health Organization and the Center for Disease Control also found that mold can be connected with a wide variety of health issues, as disparate as insomnia and fatigue.
Mold can also do a great deal of structural damage to a variety of materials. In particular, fabric can be destroyed by mold, and a key part of most mold remediation efforts is to remove any fabric that has been infested with mold.
As a general rule, and surfaces that are porous and have been infested with mold cannot be cleaned, and therefore need to be removed and destroyed. You will also need to destroy any paper products (including books).
On harder surfaces, such as wood, mold can also cause weakness. However, it is usually possible to clean surfaces such as hard, non-porous wood, and any concrete surfaces. Often, the structural damage after flooding is caused by moisture, not by mold.
Mold is very simple in terms of its needs. It needs a warm environment where it can access water. If you remove these conditions, then mold won’t survive or spread. Obviously, if you already have mold, then you will need to remove the spores that are present as well. Some hardware stores carry antifungal paint that can help keep mold from developing. Many people confused mold and mildew. Here you can learn more about mildew.
If your basement, crawl space, or another part of your house is too humid, then mold will thrive. Reducing the humidity is a good first step.
Dehumidifiers are not particularly expensive (see our guide on the best dehumidifiers you can buy) – coming in at between $200 and $300 – and will not only stop mold from spreading but will generally make your home more comfortable.
Preventing standing water is also crucial in removing the ingredients for mold to survive. Making sure your shower drains properly, or your sink doesn’t leak, for example, will very quickly help hinder the spread of mold.
If you have a constant leak or water in a place it shouldn’t be, you may need to address issues such as plumbing or the landscaping in your yard.
It is possible to tackle mold removal yourself if it is only present in a small area. Making a bleach solution with water and bleach and then wiping the area will help to kill off the mold that is there. Be sure to properly dry the area after you have finished, to prevent the mold from returning.
Also, be aware that the bleach could stain the surface you are cleaning. You could also hire mold removal professionals to clean the mold and make sure it does not return.
Most of the common stereotypes about mold are true – it does flourish in damp, humid environments, and it does grow on rotting food.
Mold also does cause respiratory problems and can also cause structural problems to various materials in your home.