Dark splotches in moist warm places in your home or office are often the telltale early signs that mold and/or mildew has found a home near you. Each of these members of the fungi family has traits that resemble each other and a few wholly unique traits.
This probably has you wondering what’s growing on your walls or woodwork. Is it mold? Is it mildew? What’s the difference?
Before we can start to truly tell them apart, were going to have to first understand the various ways they are the same.
The Similarities Between Mold & Mildew
Both mold and mildew belong to the fungi family. Each of them thrives in moist, warm conditions.
Water damage from rainstorms, a leaky roof, clogged gutters, a window that doesn’t seal properly, a basement foundation crack, or moisture left behind by plumbing problems, all offer up popular sources of moisture that both mold and mildew find inviting.
Both mold and mildew also need warmth to colonize the surface that supports them. Both are relatively benign to fully healthy adults. Yet they both can cause health problems with prolonged exposure. Especially for the very young, the elderly, and people with respiratory health conditions or a compromised immune system.
What Is Mildew?
Mildew is a member of the fungi family and is technically considered to be an early stage of mold colonization. This is probably why you see a lot of people using the terms mold and mildew interchangeably.
Just like mold, mildew is found everywhere in nature. Chances are you’ve seen it before as the strange whitish-gray, powdery substance clinging to plant leaves in the forest during hot, humid summer weather.
One of the distinct traits of mildew is that it is considered to be a type of surface fungi. In nature, it grows on organic materials like plants or food or perhaps on wood or fibrous organic materials.
In the indoor world of human homes and office buildings, mildew will often attempt to colonize fibrous materials such as:
Since it is a surface fungus with minimal root structure mildew tends to develop on the surface of something that is persistently moist, and damp. This also means that it can be easily wiped off and removed with little effort.
On its own, mildew isn’t all that dangerous. In fact, it might help reveal a previously unknown water leak somewhere in your home or office.
What Is Mold?
Mold is arguably a more well-known and robust member of the fungi family that exists in nature as well as in our indoor realm. It can range in color from green to gray, brownish and black. There are even some strains of indoor mold that can be orange or even teal green.
Mold can also vary in appearance with a texture that looks fuzzy, flat, or even slimy. Some strains of mold can even develop sickly-looking slime heads.
Green slimy mold can sometimes develop in damp, shady areas outside under your decks beneath your vinyl siding or on wood that is trapped in a perpetually shady area.
Indoor strains of mold often colonize porous substances such as grout, tile, drywall, and woodwork. You can often find mold lurking on surfaces in and around bathrooms and other areas with high humidity, consistent warmth, and poor ventilation.
Common Indoor Areas to Find Mold
Mold is commonly found in areas such as:
- Bathrooms around the sink, shower, and bathtub
- On grout & tiles
- Crawl spaces
- Poorly vented storage areas
- Ceilings where moisture is allowed to condense
- Of course, mold can easily colonize outdoor areas including wooden decks and fences that are in deeply shaded areas.
What Makes Mold Different
The thing that most differentiates mold from mildew is that it produces microscopic roots that penetrate the porous materials it germinated on. This makes mold removal and remediation more difficult.
A lot of the cleaning products sold at the consumer level simply don’t have the potency to kill mold down to its microscopic roots. Even household bleach only kills the surface of the mold, before its volatile chlorine component dissipates without fully killing the deepest recesses of the mold colony’s microscopic roots.
This means you might be able to visually wipe away mold, but its roots will continue to permeate a porous surface like wood. With the passage of time, and the recurrent presence of moisture or humidity those miniscule roots can regerminate an entirely new active mold colony.
The Hazards of Mold
Left unchecked mold can pose a variety of hazards to the structure of a home or office, not to mention pose a serious risk to the health of sensitive people inhabiting the interior space.
The presence of concentrated mold spores can respiratory irritation and sometimes even neurological issues. Sensitive people such as the very young and old or people with respiratory health conditions can have severe reactions to mold spores and the mycotoxins they carry.
This makes mold a much more serious threat than mildew. Especially if a mold colony is allowed to develop unchecked in a lesser used area like a basement crawl space or attic. The colony can then continue to thrive uninterrupted, while its spores spread throughout the interior space with increasing consequences.
As we mentioned earlier, most of the cleaning products sold at the retail level simply aren’t effective at kill mold down to the base of its microscopic roots. Compounding this problem is that most of the time when someone attempts to clean up mold on their own, they end up disturbing the colony.
This causes the mold to release even more spores into the air. Leading to more symptomatic response from vulnerable people, as well as greatly increasing the risk of new colonies developing in new areas throughout the building.
So, the safest option for dealing with a newly discovered mold problem, is to call in the professionals. Commercial grade cleaning products and industry-best mold remediation practices can then be brought to bear to clean up the mold infestation, without risk of it spreading to other areas.
You will then need to take a proactive approach to preventing future mold outbreaks. This might call for the strategic use of dehumidifiers during the summer, and using the available ventilation system to extract moisture from a room.