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Signs You May Have Toxic Mold in Your Seattle Home Crawl Space or Attic

By Mike on August 15, 2019

Discovering mold – especially toxic mold – in your home as a homeowner can be very disheartening, largely because most homeowners had no idea it was coming in the first place. Molds come in hundreds of varieties, ranging from harmless to toxic, and can be the cause of severe health complications. When you discover mold in your crawl spaces or attic it is important you identify it and quickly treat it for the health and welfare of your home and family.

Signs You May Have Toxic Mold in Your Seattle Home Crawl Space or Attic

Types of Mold (Toxic and Non-Toxic)

Molds fall into three classifications, according to the effects that they have on living things. The following are each of the classes of mold:

Allergenic Molds

Molds of this type are considered the least dangerous variety. Even so, children are more likely to be prone to allergenic molds. Mold of this variety will aggravate the symptoms of members of the household with asthma and can be very problematic to anyone in the home who is prone to mold specific allergies.

Pathogenic Molds

These types of molds are extremely toxic to individuals with weak immune systems and who are prone to infections. When exposed to mold of this type, affected individuals will display symptoms much like bacterial pneumonia.

Toxigenic Molds

Toxic molds produce mycotoxins that can carry with them severe health issues. Exposure to these molds can be absorbed by touch, ingestion or simply inhalation. The danger of these molds are so serious they have been linked to immunosuppression issues and cancer.

Identifying Mold Development

For mold to develop, the conditions must be right for it to begin developing, which include:

  • The presence of mold spores
  • Oxygen
  • Time – one or two days in the right circumstances
  • Darkness – mold cannot grow in UV light
  • Food – anything from wood to insulation or drywall depending on the mold type
  • Warmth – mold can only grow when above freezing temperatures
  • Moisture – from leaks or humidity

On this list, moisture is your number one enemy. This is also why your attics and crawl spaces are the perfect locations for mold to grow with the presence of moisture.

Visible Mold Growth

More often than not mold goes unnoticed in its early stages as it is mistaken for dust buildup or dirt. Once you become visibly aware of mold you must act with haste. Even small mold patches can spore out and spread quickly. The longer you take to address your mold problem the faster it will spread. Once you detect mold you should inspect the rest of your home, attic and crawls space to ensure that you have found it all and there is not a larger colony in the household. 

The following are several ways you can detect mold growth in your home.

Musty Smells

Most molds give off a musty smell – if you cannot see mold but you can smell it, don't ignore it! This smell is a sign that you have mold, so the longer you put this off the worse your mold situation will become.

Excessive Moisture

Signs of condensation in your home are strong signs that you have a high level of moisture in your home. This can quickly lead to mold problems as condensation escapes from your home's windows and pipes. As moisture builds up in these areas mold can quickly establish a strong foothold.

High Utility Bills

If you have utility bills that have recently taken a spike, it may be due to a leak in your home. Both water leaks and AC leaks may be the reason for these high bills and can point you to mold growth at the site of these leaks. Often leaks that were hard to detect behind walls or roof leaks will be accompanied by the presence of mold as well.

Pest Infestations

When animals gain access to your home from crawl spaces or into your attic space they often damage the homes to get in. This can allow rain water to enter these parts of your home; allowing for mold growth to begin.

Extensive Allergy Symptoms

When breathing mold spores, your body responds with allergic reactions. The more that you are in the presence of mold, the more sensitive you will become as your immune system begins to wear down from the constant attack of mold. As times goes on the allergic reactions will become worse.

Toxic Mold Causes and Prevention

Black mold is not only one of the worst molds that you can discover in your home, but it often grows where it can not be seen. Often toxic black mold is found inside walls where there has been long term moisture. Black mold requires a location that has been wet for up to a week to grow, but once it begins to colonize it will take over its environment.

The best method to prevent black mold is to not allow pockets of dense moisture to accumulate in your home (usually bath or laundry rooms), run fans to keep down condensation, and open windows to allow sunlight into rooms and open windows to reduce humidity.


You can maintain proper mold awareness by inspecting areas that might promote mold growth from time to time, as well as thoroughly clean up leaks and not allow standing water. If you discover mold and are unsure if it is toxic, assume that it might be – toxic mold carries with it long term or lifelong health effects.

If you have discovered mold in your attic or crawl space, do not hesitate to call Clean Crawls immediately, so that we can quickly schedule your home for an inspection.

Toxic Mold: Protecting Your Home From Infestation

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