Chances are that the attic is the last thing on anyone’s mind when thinking about favorite places in a home. Think about it! When’s the last time you went up there? For most of us, these designated storage spaces are only frequented when belongings need to find a new home or to drag out the holiday decor like Clark Griswald in the National Lampoon’s Christmas Vacation. Unfortunately, spiders aren’t the only thing to worry about when popping into these spaces. Attic mold can develop, causing these areas to become a contamination zone.

With how little time we spend in these rooms, that fungus among us can grow undisturbed for some time before any issue is even detected. That leads not only to more contamination within the attic but also more particles spreading throughout the entire home. Basically, it’s a home health disaster that happens far too often. 

That’s why avoiding this scenario should be at the top of every home maintenance list. The more you can do to prevent attic mold, and have a plan in place to properly address a situation should it occur to your home, the healthier you and your family will be. 

Here’s what you need to know to keep your lofty space safe. 

The Who, What, When, Where, Why, and How   

Understanding more about attics and mold separately help paint a better picture of the “why” behind each step in prevention. Here are the spark notes. 

Who and What are the Problems?

Mold is a type of fungus with over 100,000 species identified by researchers so far. It’s found all over the planet and plays a huge role in natural processes such as decomposition. When it pops up in an indoor environment, that’s when its helpful properties go way down.

When mold reproduces, it creates microscopic spores and releases them into the air.¹’² These tiny nonliving particles float around and land on any surface they come in contact with. Picture the seeds of plants and that will give you a good idea of the process. Thanks to their hardy nature, these spores only need two main components to transition into a living organism.³ 

These two elements are:

  1. A food source

  2. A moisture source 

If these are present on a surface for 24-48 hours, that mold spore will put down roots called hyphae and colonize on that surface. Once it’s all settled in, it will restart that reproductive cycle, pumping more and more spores into that surrounding area. Now, when this growth happens in nature? Not a problem because all of those particles have the entire world to disperse through. 

When it occurs in a home, that’s a much smaller space to blow around and can lead to a harmful particle buildup. It’s kind of like setting off one of the confetti cannons in sports games, except it’s set off in your attic and the confetti is small enough to ride the air current all throughout the home.

Why and Where is there Attic Mold Problem?

Obviously, the attic is the main area in question here and unfortunately, the entire space is fair game to a lucky mold spore. All it has to do is blow right in through a vent or some other tiny crack or crevice. If the conditions are right, that is. As mentioned before, a spore needs a food source and a water source to start growing.

As for food, options abound in attics. Not only are there a billion particles like skin cells and other organic matter floating around, but the building components of the attic itself can act as a food source. Just picture all of the wood, glue, drywall, and paper forming that structure. Not to mention, if the belongings tossed up there aren’t wrapped in a protective covering, these can be yummy food sources as well. 

As for food, options abound in attics. Not only are there a billion particles like skin cells and other organic matter floating around, but the building components of the attic itself can act as a food source. Just picture all of the wood, glue, drywall, and paper forming that structure. Not to mention, if the belongings tossed up there aren’t wrapped in a protective covering, these can be yummy food sources as well. 

That leaves moisture as the often missing element promoting or inhibiting growth. That being said, a leak, high humidity, or condensed moisture from exhaust vents can all create a perfect environment for this fungus among us to move into these spaces. Before you know it, attic mold will be taking over and blasting particles everywhere.

How Does Attic Mold Occur

With moisture being the main missing component, it’s important to know how this water source can pop up. But, before we get to that, a quick discussion on attics.

Attic Glossary 

For those who aren’t as familiar with attics, the explanations of how attic mold occurs can seem like gibberish. To help clear up the confusion (and to help you know what to look for during preventative steps), these are some of the top terms you need to know. 

Definition List:

  • Rafters: long wooden boards used for the frame of the roof that look like ribs

  • Sheathing: wooden boards that are fixed to the roof's joists and trusses

  • Joists: horizontal beams that run across the bottom of the space

  • Fascia boards: thin longboards that run along the lower outer edge of the roof and cover the entire roofline 

  • Roof valleys: the space where two surfaces roofs join at an angle

  • Flashings: thin material that direct water away from critical areas of the roof, wherever the roof plane meets a vertical surface, and to surround roof features, such as vents, chimneys, and skylights) 

  • Attic plumbing stacks: A vertical pipe connected with all vent pipes carrying off-gasses from a building

Causes of Attic Mold

Some of the top factors that lead to attic mold include: 

  • Roof Leaks: Holes from a storm blowing debris around, broken shingles, improperly installed gutters, and chimney damage can all lead to moisture making its way into the attic.
  • Improper Exhaust: These systems are designed to take moisture-filled air out of areas like kitchens and bathrooms. If they lead to the inside of the attic instead of directly outside, that wet, hot air will increase the humidity inside of an attic and can form condensation wherever the exhaust vent ends.

  • Ventilation Issues: Attics typically have passive ventilation systems, where the outside air comes in through soffit vents and then releases this air through vents at the top of the space. If the vents are blocked or if there aren’t enough for the size of the space, this airflow will not occur and the hot, humid air will remain inside, allowing moisture to build up and for mold to grow.

Any of these scenarios can allow moisture in and with food sources in abundance, any mold spore that made it into the attic space will think it won the lottery dream home. Once it’s thriving, that can cause a long list of health issues for you and your family. 

The Issue with Attic Mold

Mold isn’t just an unsightly home pest, it can also wreak havoc on the body when it colonizes a home. As mentioned earlier, once a mold colony settles in, it begins to release microscopy spores into the area. Some species of mold also create microscopic toxins called mycotoxins when threatened, further adding to the particle party.⁴  

And, to make it even more interesting, where mold goes, bacteria often follow. This organism also creates microscopic particles, which, you probably guessed it, add even more particles to the indoor space. Mold spores, mycotoxins, and bacteria, oh my! Right? 

The key thing to understand as to why this contamination event is a health hazard is the size of the particles in question. They’re so small that they can be inhaled, ingested, or absorbed into the body and are measured in a unit of measurement called microns. A micron is 1,000 of a millimeter, meaning you’d have to line up a thousand microns to equal the distance between the two little lines on a ruler. 

The EPA termed these specific types of tiny specks as particulate matter and further classified them into two categories.⁵ 

These categories include: 

  • PM10: particles that have a diameter of around 10 micrometers or less.

  • PM2.5: fine particles that have a diameter of around 2.5 micrometers or less.

When you encounter a few of these particles throughout the day, whether walking into work or driving down the street, the body tags these little guys as foreign invaders and sends the immune system to get rid of them ASAP. Growth inside of a home is nowhere near this level of exposure.

Issues like attic mold mean that all of the particles released by mold are confined within the walls of the building, not floating around in nature. Thanks to current building practices pushing for net-zero energy efficiency, there’s also limited airflow between the inside and outside environments, meaning that a majority of these particles will remain indoors unless physically removed. 

The longer someone is in a home with attic mold, the more particles will enter the body with every breath taken or surface touched. The immune system will attempt to keep up, but it can get overloaded or malfunction.⁶’⁷’⁸’⁹’¹⁰ This results in a long list of symptoms and related autoimmune conditions such as Chronic Fatigue Syndrome, candida, Aspergillosis, and the Epstein-Barr Virus.

A few common symptoms of exposure include: 

  • Digestive issues

  • Rashes

  • Muscle and joint pain 

  • Hair loss

  • Chronic fatigue 

  • Brain fog

  • Headaches and/or migraines

  • Respiratory problems 

  • Coughing 

  • Mood swings

  • Anxiety and/or depression 

  • Hormonal imbalances

The tricky thing about exposure, though, is that no two people respond the same way. While one person may experience the occasional reoccurring sinus infection, another may develop an autoimmune condition and 30 symptoms. Researchers are hard at work attempting to figure out how and to what extent exposure impacts the body and immune system, but it’s a tough subject to nail down for a variety of factors. 

Some of these include:

  • Genetics

  • Immune system status (compromised and developing immune systems are at greater risk for reactions)

  • Species of mold

  • Presence of mycotoxins

  • Presence of bacteria

  • Length of exposure

  • Volume of particles present 

Still, the increase in the toxic load of the body from exposure and potential symptoms is reason enough to actively work to prevent issues such as attic mold.

How to Prevent Attic Mold  

The best way to tackle attic mold is to prevent it from ever popping up in these spaces in the first place. For those with limited attic knowledge, make sure the definitions above can help explain a few of these preventative measures.

Ways to prevent attic mold include: 

  • Check the roof for leaks: This should be done bi-annually at least, but the more often the better. The sooner you can catch a leak, the less moisture will be able to enter the attic. A lack of moisture means a lack of microbial growth. If any issues are found, get them fixed ASAP and make sure to check the attic for any water damage or mold growth. 

  • Make sure there’s proper ventilation: Without a steady airflow, humid air can get trapped inside the attic, creating the perfect conditions for mold growth. Checking for ventilation includes making sure that there are enough vents and that they’re not blocked by things like insulation. An easy trick is to check during the daytime- turn off all the lights and look for sunlight coming in through both the top and bottom vents. As for whether or not there are enough vents, check with your local building codes for mandatory requirements. The U.S. Federal Housing Authority recommends a minimum of 1 square foot of attic ventilation for every 300 square ft but ventilation requirements can change from region to region.
  • Take a look at the exhaust vent location: All exhaust vents from bathrooms and kitchens should vent outside of the home, not in the attic. If all of that warm, humid air ends up in the attic, it can lead to condensation in the space, allowing for mold to grow. They also shouldn’t vent directly under the roofline because it can get sucked right in through the vent and into the attic space. 
  • Inspect the space: At least four times a year, grab a flashlight and take a close look at the interior of the attic space. Make sure to not only check for mold but also for water damage and blocked vents as well. 
  • Check furnaces and water heaters: This involves making sure that they’re in a properly insulated room and meet code requirements. It’s also a good idea to get these serviced 1-2 times a year to make sure they’re operating correctly. 
  • Clean gutters regularly: This helps prevent water from overflowing into the attic and the home in general. 
  • Try to limit storage: Keep the attic free from as many belongings as possible. The less there is up there, the fewer food sources for mold and the better the airflow will be. More airflow means less trapped moisture. 
  • Make sure the insulation is top-notch: If insulation is not installed correctly throughout the entire space, it can lead to improper airflow in the attic and trap moisture. Both situations can end up leading to mold growth.

If you’re just not sure or want to go the extra mile to make sure that your attic is set up for success, contact an attic expert to come in and check out the space. 

How to Tell if You Have Attic Mold

Checking mold attic mold is a comprehensive process so make sure to grab a flashlight and use those senses. 

Do a Visual Inspection

Use that flashlight and look at every little crack and crevice in the space. Keep in mind that you’re not only looking for mold but also water damage as well.

When it comes to visible mold, look for any discoloration or abnormalities. With so many species out there, mold can come in all sorts of colors, shapes, and textures, so look for any sort of abnormality. Some of the most common colors include green, white, grey, blue, red, black, brown, or the infamous pink. As for textures, they could be fuzzy, powdery, velvety, or slimy.

As for water damage, visible issues that indicate a moisture problem include:

  • Dark stains on plywood

  • Wet insulation 

  • Water spots on ceilings

  • Rusty nails 

  • Frost buildup underneath the roof 

Some of the top areas to check for problems include rafters, joists, fascia boards, roof valleys, skylights, chimneys, windows, flashings, attic plumbing stacks, air conditioners, and vapor barriers. 

Another tip: If you discover water dripping from smoke detectors, bath fans, and light fixtures, that points to a moisture problem in the attic. Watery problems are moldy opportunities.

Does it Smell Up There?

If you don’t find any visible mold, that doesn’t mean that there isn’t a problem. The growth could be in a hidden location like beneath insulation or too small to be visible yet. 

In this case, rely on your nose. Mold growth often creates a damp, musty, earthy smell due to the release of gases called microbial volatile organic compounds (MVOC).¹¹ If you smell this in the space, there’s a good chance that you’re dealing with attic mold. 

How Do You Feel?

To make matters more tricky, not all mold growth will be visible, and not all mold growth will create a smell. In cases like this, pay attention to your body and how you feel. Have you developed chronic symptoms over time that no doctor can pinpoint a root cause for? Do they flare up anytime you go into the attic? 

Our bodies are amazing warning systems that will let us know when something is wrong. If you start feeling unwell, those invisible particles could be making their way inside of your body and wreaking havoc, causing your body to sound the alarm and push for you to get out of that situation. Always listen to your body when it’s saying, “Hey something is definitely not right here”

How to Get Rid of Attic Mold

When attic mold pops up, it needs to be taken care of properly and quickly. The longer it’s there’ the more contamination there will be around the space and throughout the home. And, the more spores there are in a home, the higher the chances of another mold problem developing elsewhere.

That being said, the absolute best option for dealing with mold is hiring a team of professionals to handle it. With all of the semi-porous and porous surfaces in the attic, it’s an extensive process to remove the contamination. Remember that mold grows roots, which can reach deep within these surfaces. Proper remediation should also include fixing the issue that led to the growth in the first place and installing engineering controls to make sure particles aren’t getting blasted all over the place.

First up should be a qualified mold inspector. This individual will go through the entire home, determine if that’s the only problematic area, figure out what led to the growth in the first place, and alert you to what contaminants are present including species of mold, mycotoxins, and/or bacteria. 

With this information, a qualified remediation team will be able to come in and properly eliminate the contamination so that the home is once again safe for you and your family. A team with this priority in mind should ensure that its remediation protocol is based on three pillars. 

These pillars include: 

  1. Remediate the sources and mold properly 
  2. Identify and address the problems that led to the sources in the first place (otherwise, the mold will just grow back)
  3. Eradicate all contamination that exists from the mold problem, including mycotoxins and bacteria

If any of the boxes above aren’t checked off, the mold could grow right back or contaminants like dead mold or mycotoxins could be left behind, leading to prolonged exposure.

Keeping It Dry, Fresh, and Airy

Unless you’ve tackled a serious renovation to make the attic a living space, these lofty areas are pretty much out of sight out of mind. But, they’re still a part of our homes, so we’ve got to actively include them in home maintenance. Bringing our indoor spaces into the wellness conversation will bring us that much closer to bettering our overall wellbeing.

Building awareness of all things attic mold, including prevention and an action plan, can help ensure that you and your family remain safe inside your home. The fewer particles there are floating around inside, the easier you’ll breathe and the happier your body will be. A happy, balanced body leads to a happier and healthier you. 

Health begins at home.™


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