Why Is There Mold in My Attic? Is It Dangerous?

22 March 2023

Ground Level View of a Dirty Attic

Mould can appear in any part of your home, as long as there are suitable conditions for its growth.

Attics often provide the optimal conditions for mould growth, so these tend to be among the most common spaces where mould appears.

More often than not, attic mould grows uninhibited and undisturbed for years, as many homeowners rarely go up in their attic. That’s why regular mould inspection services are an important part of taking care of your home, as this can uncover a problem before it causes severe damage.

But is attic mould hazardous? What causes it in the first place? Read on to find out.


What Causes Attic Mold?

man working on attic insulation roof

Excessive moisture is the most frequent cause of attic mould because it fosters the growth and spread of mould spores. The following are some of the most typical reasons for dampness in attics:

  • Without proper ventilation, moisture buildup in your attic is practically inevitable. Without sufficient ventilation, warm, humid air from the lower living areas can ascend into the attic and condense on surfaces, which can encourage the formation of mould. Air circulation from proper ventilation keeps the attic dry and helps to avoid moisture buildup.

  • Mould growth in the attic is frequently brought on by roof leaks. With cracked or missing shingles, flashing, or other roof elements, water can get into the attic. As a result, moisture may accumulate, creating the perfect conditions for the growth of mould. Mould growth can be stopped with routine roof maintenance, such as replacing worn-out shingles or fixing leaks.

  • Warm, moist air that comes into touch with cooler surfaces condenses. This can occur in the attic as heated air rises into the cooler attic from the living spaces below. Condensation can happen on surfaces like roof sheathing if the attic is improperly insulated, which can cause moisture buildup and mould growth. Condensation can be avoided and the attic can remain dry with proper insulation.

  • If plumbing lines or HVAC ducts that pass through the attic leak or condensate, the result might be moisture buildup and mould development. Inspecting and maintaining these systems on a regular basis can assist find leaks before they result in mould growth.

  • Mold growth in the attic is occasionally caused by inadequate insulation. Warm air from the living areas below can leak through inadequate insulation, causing condensation on attic surfaces that can eventually turn into mould. More insulation can aid in keeping the attic dry and help stop moisture buildup.


Signs That You Have Mould in Your Attic


empty attic

To ensure that mould doesn’t grow for too long in your attic, you should be on the lookout for the following signs:


Musty Odours

Mould frequently emits a characteristic odour that is typically characterized as musty, earthy, or wet. If you notice this smell in your attic, there is probably mould developing there. If the mould has spread throughout your house, you might also detect the scent in other places.


Visible Mould Growths

Mould can develop on a variety of surfaces, including floors, walls, insulation, and ceilings. You most likely have a mould issue if you notice any indications of mould development in the attic, such as black, brown, green, or white spots or patches. It’s crucial to contact a professional to perform a comprehensive check because mould may occasionally be concealed behind walls or in insulation.


Water Damage

Mould requires moisture to flourish, thus there is a greater danger of mould growth if there has been any water damage in your attic, such as a leaky roof or burst pipe. Keep an eye out for indications of water damage, such as stains, discolouration, or surface warping.


Discolouration of Surfaces

On surfaces where it grows, mould can discolour them. For instance, you might have mould development if you see black or green stains on the walls or ceiling. Insulation that has been affected by mould may also seem soiled or discoloured.


Allergic Reactions

Any sign of mould allergies, like if you or a member of your family develops symptoms while in the attic, such as sneezing, coughing, itchy eyes, or a runny nose could indicate the presence of mould. More severe symptoms, such as headaches, exhaustion, or breathing difficulties, may also be experienced by some persons. To avoid further health issues, it’s critical to handle the situation quickly if you suspect mould allergies.

Should You Ignore Mold in the Attic?

attic source of moldMany people think that attic mould isn’t dangerous, as it’s up there in a room where they don’t spend too much time.

Mould spores can’t travel against the flow of hot air rising in your home very easily (known as the Stack Effect), therefore they have a hard time making their way into the rest of the home on the floors below, and rarely show up in an air quality test in those rooms, except in the most extreme cases of attic mould.

So, should you ignore attic mould if it isn’t likely to affect the rest of your home?

The simple answer to that is no. Even if attic mould has a hard time spreading to other parts of the home, it can lead to the deterioration of attic sheathing and roof structures that is compounded by the moisture in the attic. If left untreated, this deterioration can lead to small roof leaks becoming more severe, and even lead to your roof collapsing.

If you don’t hire a professional for regular mould inspection services, you won’t find out that there is a small mould problem that can be fixed with a smaller mould removal job. That small problem will eventually become a bigger problem that will require a larger mold remediation job and roofing repairs that are more costly to complete.

Call the mould removal professionals at First Response immediately to perform a mould inspection and mold remediation. We will take proper measures to ensure that your indoor air quality is safe and optimal once again.

Do you have a major mould problem, or hazardous mess
that needs a professional extreme deep cleaning crew?

Contact First Response Cleaning today to take care of it!

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Dangers of Mold in the Attic

Even though attic mould doesn’t pose as great of a health risk as mould found in other parts of the home, mould exposure of any kind can cause serious health problems, especially after years of exposure.

According to the CDC, mould can lead to:

Allergy Symptoms

Mould exposure can lead to irritation in the eyes, nose and skin. Symptoms that come with mould exposure are often mistaken for allergies, like itchy, watery eyes, runny nose, sneezing and skin rashes. Because people often think their symptoms are from allergies, they don’t consider that their symptoms could be caused by mould exposure and don’t see the need for a mould inspection. This is a big mistake as this kind of thinking leads to mould issues not being fixed before they get worse, causing worsening symptoms and more damage to their home.

Respiratory Issues

ladder to attic inspecting for mold
As people exposed to mould in their homes breathe in toxic spores, they may begin to experience respiratory issues. Respiratory symptoms caused by mould exposure include coughing and wheezing, shortness of breath, upper respiratory tract infections, more frequent and severe asthma attacks and other respiratory problems.

Severe Health Issues

In the most severe, and long-term cases of mould exposure, people can begin to experience a weakened immune system, making them more susceptible to diseases and illnesses caused by bacterial and viral infections that can impact them much more severely and take longer to recover from than normal. The toxic effects of prolonged mould exposure can also lead to neurological damage and death. That’s why regular mould inspections and mould remediation is vital to protecting your health.

First Response – Trusted Mold Removal Experts

Attic mould removal isn’t something you should do on your own. You could risk inhaling mould spores, as well as spreading them through your home by tracking spores into other parts of your home on your clothing or cleaning tools. Also, regular cleaning products you find under the kitchen sink can’t remove mould effectively. Using these products often leads to mould spores being released into the air and spreading through the home, as well as growing back in the place you tried to clean.

That’s why it’s best to contact indoor air quality and mould removal professionals who can perform mould remediation properly.

First Response Cleaning is your go-to partner for expert mold remediation across Ottawa and Eastern Ontario. We have the right expertise, experience and specialized equipment for removing mould safely and effectively.

We can inspect your entire home for mold, as well as conduct thorough air quality testing to check for any other contaminants that should be remediated.

Our indoor air quality tests include checking for biological, chemical, and radiological pollutants. If we detect any, we will provide you with thorough air quality treatment services.

We hire experienced indoor air quality pros for our team – meticulous, highly-trained, certified, and experienced. You can rest assured knowing they’ll return your home to its natural, healthy state through expert mold remediation services.

Contact us today to schedule an inspection.