Protecting Your Home from Outdoor Black Mold: What You Need to Know


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One of the most important tasks regarding homeownership is ensuring your home remains safe and secure. Unfortunately, black mold outside of the house can be a major problem many people face without even realizing it.

Black mold grows in damp areas and thrives on organic materials such as wood or paper-based products; therefore, any area with moisture near these items is susceptible to an infestation.

Identifying the causes and signs of black mold exposure will help you take preventative measures before more serious damage occurs.

In this blog post, we’ll discuss what exactly black mold is, common causes for its growth outdoors around your property line or foundation walls, symptoms associated with exposure so you know when there may be a potential issue at hand, tips for cleaning up existing outdoor black mold yourself if necessary, as well as professional services available, should things become too severe.

Causes of Black Mold Outside the Home

You may think that rain and snow are the only potential causes of black mold outside your home, but think again. We'll also cover other less-recognized causes of mold below.

The most common cause of black mold outside the home is water damage due to rain and snow. This can lead to water pooling around foundations, siding, windowsills, and other areas where it can seep into a building’s interior.

Improperly Aimed Sprinklers Can Cause Mold

Sprinkler systems that spray onto buildings. The water from your sprinklers should never be allowed to reach the side or roof of your home and should never be allowed to pool anywhere in your yard, especially close to your foundation. When the outside of your home remains wet, the inside of those walls will be wet, too.

Full Gutters Can Cause Mold

full house gutters

If you don't clean your gutters out regularly, they collect leaves, dirt, and debris. When leaves begin to decay, they've become a breeding ground for mold that can spread to your roof and walls. To remain effective and mold-free, you should clean your gutters once in the spring and again during the fall.

To reduce your risk for black mold growth outside your home, ensure all potential moisture sources are properly sealed off from entering your living space.

You should also inspect any exterior surfaces regularly for signs of water damage and repair them immediately if found.

Finally, keep an eye on the outdoor temperature and humidity levels so that they do not become too extreme, which could lead to condensation forming inside walls or ceilings; this would be a prime environment for black mold growth.

Plants Close To Your House Can Cause Mold

Plants hold moisture and if you have plants too close to the exterior of your home, it can cause mold there. You shouldn't have anything growing along the exterior of your house, either; vining plants and moss may give your home the old cottage look you want, but they're bad for the structure of the building.

Not Having Any Mulch Can Cause Mold

When dirt and grass grow directly up against your home's side, rain splashes dirt on it. Dirt contains mold spores and goes up the side of the house. Pine and cedar mulch, in particular, are best to use if you have mold concerns and still want to use a natural mulch product. If you don't care about using a natural product, rubber mulch is a better alternative because it's inorganic and discourages mold growth.

How To Remove & Clean Up Existing Outdoor Black Mold

removing black mold from house

Take Safety Precautions For Removing Outdoor Black Mold

Wear protective clothing such as long-sleeved shirts, pants, gloves, and a face mask or respirator when working with mold. Avoid breathing in any spores that may be released during the removal process.

The fact that the mold is outside of your home may make these precautions seem like overkill, but even outside you run the risk of exposing yourself to mold, because it's being made airborne by the cleaning process.


Identify The Source of Moisture

The first step in removing outdoor black mold is to identify the source of moisture that caused it to grow in the first place. This could include damaged roof tiles, roof leaks, clogged gutters, damage to your home's exterior, poor drainage around your home’s foundation, or other water intrusions into your home’s exterior walls and siding.

Sources of moisture can include, but aren't limited to:

  • Damaged roof tiles
  • Roof leaks
  • Clogged gutters
  • Home exterior damage
  • Poor drainage around the foundation

Fix The Source of Moisture (If Possible)

If the source of the moisture is something you can fix, repair it immediately before beginning any remediation efforts on the affected areas outside your home.


Use A Pressure Washer

pressure washing roof tiles

Next, use a pressure washer with a cleaning solution specifically designed for killing mold spores on hard surfaces like concrete walkways and driveways, as well as wood decks and fences. You can use a commercial cleaning solution or you can use diluted bleach.

For non-porous materials, use a bleach solution (1 part bleach/3 parts water) applied with a quality pump sprayer like this one on Amazon, followed by rinsing off with clean water afterward.


Let The Home Exterior Dry

Allow all treated surfaces to dry completely before proceeding further with cleanup efforts inside your home if necessary due to extensive damage from flooding or seepage through interior walls etc.

FAQs in Relation to Black Mold Outside of House

What causes black mold on the outside of a house?

Black mold on the outside of a house is typically caused by moisture buildup. This can be due to inadequate ventilation, high humidity levels, or water damage from flooding or leaking pipes. Moisture and warm temperatures create an ideal environment for mold growth.

How do I get rid of black mold outside my house?

Removing black mold from the outside of your house requires a few steps. First, identify and remove any sources of moisture that may be causing the mold growth. This could include repairing leaking pipes or gutters, sealing windows and doors to prevent water infiltration, or redirecting downspouts away from the home's foundation.

Once these issues are addressed, use a bleach solution to scrub visible mold on hard surfaces like siding and brickwork. Finally, use an anti-fungal spray to help prevent future mold growth in areas where moisture can accumulate again. Note that if the cause of the mold isn't dealt with, it will return.

Can black mold grow on the outside of a house?

Yes, black mold can grow on the outside of a house. It is most commonly found in areas exposed to moisture, such as around windows and doors, or near air conditioning units. Mold spores need an organic material to feed on and moisture for growth, so if these conditions exist, black mold can form on a home's exterior. Regularly inspecting your home’s exterior can help you identify any potential issues before they become problems.

What does mold on the outside of a house mean?

Mold on the outside of a house typically indicates an underlying moisture issue. This could be due to various issues, from sprinklers wetting the house, clogged gutters, water pooling around the foundation, etc. If left untreated, mold can cause structural damage and health risks for home residents. It's important to address any water damage or mold growth quickly By calling a professional restoration and remediation contractor who can identify the source of the problem and provide solutions to prevent further damage.


In conclusion, black mold outside the house can be a serious problem requiring professional remediation services. If you suspect your home has been affected by outdoor black mold, it is important to take the necessary steps to identify and remove the issue as soon as possible. Professional water damage restoration and mold remediation contractors are experienced in dealing with these issues. They can help ensure your home is safe from further contamination or health risks associated with black mold exposure.

Are you dealing with black mold outside your Orlando, Florida house? Don't wait any longer to get the help you need! Damage Control 911 provides water damage restoration and mold remediation services to protect your home from further damage. We have years of experience handling water damage and black mold growth issues in homes. Contact us today for an assessment.

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