Black mold in attic

Usually, the spores have no negative affects when they enter the house. However, if there is a damp or wet spot, the spores can begin to reproduce resulting in mold. Unfortunately, molds can cause health problems when inside a home. Often, molds produce allergens, irritants, and in certain molds even toxic substances known as mycotoxins. For those with asthma, it can trigger severe asthmatic attacks. In addition to the health hazards that mold causes, it can also damage surfaces. Wood, fabric, and leather can be discolored and suffer from long term damage when exposed to mold. It strives anywhere where there is warm, damp air, and as a result, attics are often at risk of hosting mould.

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Different types of mold

Molds come in different sizes, but the health and aesthetic concerns are all the same. They are named according to the colors they grow displaying. They include:

White mold

It thrives in dark and wet areas. Mostly, white fungi is confused for efflorescence because they share the same color. However, white fungi have a musty odor and will develop on wood, concrete, sheet-rock as long as the conditions from growth are met.

Black mold

It grows in moist and warm places. Typically, it appears in black spots cramped in one area and continues to spread if left untreated. Black molds are said to be toxic and causes health hazards.

Green mold

Appears in a green-grayish color that could signal the presence of Penicillium, Cladosporium or Aspergillus. These types of fungi thrive in cool environments such as damp areas found indoors or on rotting food in the refrigerator.

Yellow mold

It is highly toxic and should be eradicated as soon as possible. If it touches the skin, inhaled or consumed, it can cause severe health complications. Yellow fungi is usually found on wood and can cause a great deal of damage if left untreated.

What causes black mold in attic?

Fungi, specifically black mold, is often found in attics for a variety of different reasons. Due to your attic being the closest thing to the roof of your house, any moisture will end up there resulting in black or white mold. However, the cause of a house actually have a black mold problem can be caused by a plethora of different issues.

Poor attic ventilation
Not enough ventilation in the attic is the most common reason for black mold being found in attics in places with cold climates. Additionally, poorly designed attic ventilation can be just as problematic. Some attic ventilation systems are designed so that there is a combination of vents that trap and create pockets of “dead air” that is created from condensation of the decking of the roof in cold temperatures.

Wrongful dischargement
Unfortunately, some house designs leave the vents from the dryer, kitchen, bathroom, and other types of exhaust fans in places that cause them to release their discharge into the attic instead of the outside of the house. This can create the perfect setting for black mold.

Condensation by the furnace and water heater
If a furnace and or water heater are set up in a attic with poor ventilation instead of an enclosed area, they can give off enough heat to create condensation in cold temperatures and contribute to mold growth.

Floor insulation
If the floor below the attic is either missing floor insulation, or has a poor moisture barrier installed, heat and moisture from the house and rise into the attic area. This process can lead to the growth of black mildew, especially in cold temperatures.

Leaking roof
If the roof is leaking, you’re definitely in trouble. If the roof is leaking, the area of black mold will typically be directly below where the leak is. However, if your attic has poor ventilation, the mold can spread to other areas of the attic.

Is mold in the attic dangerous?

Yes, it could be. Although there are no health problems directly linked to attic mold, it can lead to flares of allergies and asthma. Luckily, attic mold rarely finds its way into the building because of the ‘stack effect.’ This refers to the upward movement of air currents in your house. When warm air rises in your home, it reaches the attic carrying the mold spores. From here, they are eliminated through the venting, which means that they do not get to affect the occupants of the home. Since these movements are not likely to be reversed, most households are safe from attic mold. If the attic mold finds its way into your house, however, it could pose some health risks.

Is mold in attic common?

Yes, attic mold is common because it can be found in any property, old or new. The condition for the growth of mold is abnormal moisture levels in the attic. Although attic mold can be found in all homes, research has shown that older homes are at a higher risk of attic mold infestation. This is because they often have faulty insulation that allows moisture to penetrate, thus creating suitable conditions for mold growth. The most common type of mold that grows in attics is Penicillium and Aspergillus.

Does attic mold spread into your house?

Yes, attic mold can spread into your house. The spread of attic mold is through spores because it is light and easy to carry in the air. When warm air rises in your home, it escapes through the attic, leaving a vacuum behind. The vacuum is then covered by air from the basement and crawl space that contains impurities like dust mites, mold spores, and odors. Once the mold spores find their way into your house, they will spread rapidly throughout other rooms, thus causing a mold infestation. Mold spores could cause an outbreak 7 to 14 days after exposure.

Can mold in the attic make you sick?

No, it cannot. Fortunately, attic mold is not associated with the negative health issues that are linked to other forms of molds. This is because people do not spend a lot of time in the attic. As such, they do not get to breathe in mold spores that cause health problems. However, this does not mean that attic mold is safe. It could still be harmful to the occupants of your home. If not monitored, attic mold growth can cause an infestation that can pose health risks for people with allergies and other health conditions like asthma. In some instances, breathing attic mold spores can cause persistent coughing, sore throat, and sneezing.

Mold in attic insulation

Technically, the attic insulation cannot support the growth of fungi. The black fungi does not grow on the attic insulation itself. The most legit explanation to why you might find fungi growth on the top surface of attic insulation is because the dust that drops from the roof sheathing settles on the top on the insulation. The dust may create an adequate ground for black fungi growth. See also our article: Black Mold on Insulation.

Attic mold removal

It’s important to remove mold that you find in your attic. Mold can have harmful health effects for those sensitive to allergens. Thankfully, unless the damage is too great, most furnishings and items can be salvaged. Mold can be removed using simply water and a light detergent, a wet vacuum, a bleach/water solution, or high-efficiency particulate air vacuum. If an item has small crevices or pores, it might be best to throw it away as mold can be extremely hard to remove from those spaces.

How to remove mold in attic?

• Step 1: Fixing the source of moisture into your attic.
  This will ensure that you prevent the growth of mold. Not addressing the source of moisture can cause regrowth of mold in your attic.
• Step 2: Remove the items in your attic.
  If you use your loft for storage, ensure that you remove all the items stored and disinfect them with vinegar to kill all the mold spores. Do a general cleaning in your attic and identify the areas with mold growth.
• Step 3: Spray with vinegar/bleach.
  You can use bleach or vinegar to clean the mold on your attic. When using vinegar, ensure that you use personal protective gear because it has a scorching effect on your body. When using bleach, be sure to mix it with warm water in a ratio of one cup of bleach to a gallon of lukewarm water.
• Step 4: Do away with infected items.
  You should not return items that have mold into your attic without thoroughly cleaning them. This is because they might contain spores, which will cause a re-infestation.

Attic mold remediation

Once you notice black fungi growing in one part of the attic, there could be a probability that it has been spreading to other areas. Be sure to inspect the entire area to rule out the possibility of other fungi-affected areas.

Also, inspect the cause of black fungi growth and fix it. This includes ensuring that the roof has no leaks, the insulation is adequately ventilated and insulated and repair or removal any loose roof gutters.

In this case, the only solution to destroying all the fungi in the insulation area the removal of all moldy insulation. The wood affected should be replaced with fresh material free from fungi.

As for the wood that cannot be eliminated, such as the support beams, they should be treated to thorough sanding and sealant application to prevent any fungi from re-growing. Any other molded material in the affected area must be cleaned, discarded or replaced.

Remediation cost

Attics come in various sizes, black mold damage and construction complexity. Majority of attic fungi removal and remediation services will cost around $10 to $25 per square foot. It wouldn’t be fair to charge according to area size, so most professionals will inspect the severity of fungi growth and attic damage and later give the cost of remediation. An entire budget for attic fungi removal and remediation may cost you from about $1000 to $4000 exclusion of any roof repairs.

Attic mold prevention tips

Whether you’ve found black mould in your attic and want to prevent it from spreading further, or if you’re simply just concerned about mold in the attic becoming a problem, there are steps you can take to ensure that black mould in attics won’t be in your nightmares.

• Correct insulation – If you find that there’s missing insulation between the attic and the below living space, make sure to install some. This will keep the cause of the black mildew from reaching the attic and causing the problem.
• Enclose furnaces and water heaters – Make sure that furnaces and water heaters are enclosed in an insulated area, whether it be a closet or seperate room. If there are vent pipes or exhaust systems that have to go through the attic, the area in the attic needs to be double or triple wall ‘B’ vent type to help prevent black mold.
• Correct ventilation – The best way to prevent black mold in your attic is to make sure that it has properly balanced ventilation. Ideally, the ventilation in the attic would have ports that are evenly split between the upper and lower portion of the roof.

Other measures to prevent black mold from forming in your attic include immediately fixing a leaky roof, make sure that dryer and other vents aren’t discharging into the attic, and insulating pull down stairs and other entrances into the attic.

Protective gear

When removing mould, it’s important to make sure that you avoid contact with the mold as well as avoid inhaling any spores. When working with mould, be sure to wear protective clothing so that no spores ends up on your clothes. Also, it’s advised to wear a N-95 respirator as well as gloves, and properly fitted goggles.

When working on black mold removal, use extreme caution and don’t slack on protective gear. Precautions need to be taken to take you, those around you, and the environment as safe as possible.

Reduce the chances of mold with proper attic ventilation

One of the biggest causes of mold is having improper ventilation in your attic. This is intensified during the winter months when there is a significant amount of air coming in your attic versus going out. There is also a temperature variance that will create moisture buildup if not properly taken care of.

The heat leaking out of your house and into the attic combined with the already cool or cold temperatures in your attic will cause condensation. This condensation if occurring for a prolonged period of time can lead to mold growth. The worst part of all of this is that how many times a year do you go in your attic? If you are like most people very rarely. This gives the mold ample time to grow and spread. Greatly increasing the likelihood that you or your family with possibly get sick with mold poisoning.

Another important item to check is if you have a bathroom ceiling fan vent or even a dryer vent running directly into your attic. This will create and instant surge of moisture as the hot moist air is cooled by the attic air.

Another important step is to seal up any gaps around pipes or chimneys that go through your attic. This is a critical place that air can escape into your attic.

It is recommended that if you have any concerns about proper insulation you should consult a contractor. If you suspect you may have mold issues contact a certified mold inspector who can come in and run a series of tests to determine if you have a mold problem and the extent of the issue. If you do have mold or black mold that is more than a 10ft by 10ft area you should call a black mold removal professional to give you a quote on the removal costs and setup an action plan.