What Is Orange Mold & Is It Dangerous? | Orange Mold Facts

Mold is common all around the world, but orange mold? It’s not as popular as other species when it comes to researching it. With our years of experience in mold identification and detection, we’ve learned a whole lot about orange mold. Let’s explore the critical details, including potential health effects.

Mold is everywhere in our lives: in our food, in our gardens, and sometimes even in our medicines. However, not all mold has the same effect on our health. Some molds have no effect or even a positive effect, while others can be extremely harmful.

Being aware of the many different varieties of mold as well as the health risks of each makes you more capable of protecting your health and the health of the people you love.

What is orange mold?

what is orange mold

When most people think of mold, they imagine its most common household forms, which tend to be either black, green or white.

However, molds are incredibly diverse and can occur in all kinds of different shapes, sizes, textures and colours. What people refer to as “orange mold” is any of a variety of mold species that can present with orange colours. These species include Fuligo septica, Aleuria aurantia and many others.

orange mold in bathroom
orange mold in bathroom

What does orange mold look like?

Orange mold differs from other types of mold in more ways than just its colour. One of the biggest ways that orange mold differs from more common types of mold is its texture.

While most molds have a furry texture, orange mold usually appears with a slimy, spongy consistency. One of the most common (and memorable) species of orange mold is Fuligo septica, more commonly known as “Dog vomit slime mold”. It looks just the way it sounds and grows well on wood, most frequently on mulch piles in gardens.

Pictures of orange mold

What causes orange mold?

As with all other types of mold, orange mold grows wherever there is moisture, heat and a food source. However, orange mold differs from other types because it is more likely to grow on wood than other organic materials.

Knowing this, you should be especially vigilant about orange mold growth in areas of your home with high humidity and lots of wood.

orange mold on walls
orange mold on walls

Wooden window sills are magnets for orange mold, as well as exposed structural beams in basements. Attics are also havens for orange mold growth because they collect warm air and moisture that rises from the rest of the house and they usually have exposed rafters.

Finally, your kitchen is a hotbed for orange mold growth; wood in the floor and especially in the ceiling above the stove are vulnerable to orange mold growth.

What are the health risks of orange mold?

You may have heard certain molds associated with certain diseases (e.g., black mold and cancer), but contrary to popular belief, mold doesn’t affect everyone the same way.

Some people are allergic to mold and may experience symptoms ranging from congestion and itchiness to full-blown anaphylactic shock. Others may experience mild symptoms like headaches, while others can be made seriously ill with cancer or even neurological disorders.

orange mold in basement
orange mold in basement

The health risks of mold exposure for a particular individual will depend on four factors:

  1. The type of mold: Not all species of mold are harmful to humans, and yet others can be fatal with minimal exposure. Many species with vastly different health risks present with the same colour and even consistency, so species of mold can’t be identified with any kind of certainty upon visual inspection. If you notice mold in your home, you should have a sample collected by qualified mold professionals for testing at a third-party laboratory.
  2. The severity of infestation: A few mold spots around your windowsill won’t cause much harm, but a mold infestation covering more than a few square feet can cause serious illness. However, it is important not to estimate the severity of infestation based solely on what you see. Mold often hides in walls, attics and floors, meaning that the mold you see is just the tip of the iceberg. If you think your home may be infested with mold, you should have it inspected by certified mold expert, who can use sophisticated equipment and techniques (e.g., air testing, infrared scanning) to determine just how much mold is growing in your home.
  3. The length of exposure: As with any harmful pathogen, the health risks of mold will vary depending on how long you are exposed to it. A few hours in a moldy house likely won’t cause serious problems, whereas spending several hours a day for years in a moldy house can be extremely detrimental to your health. The only way to be sure that you are not suffering from long-term exposure is to have your home’s air quality tested by a reputable mold testing company.
  4. The health of the people being exposed: People with weakened immune systems—such as children, the elderly and people already suffering from serious illnesses—will be more susceptible to mold-related illnesses. In the case of toxic mold, children are more vulnerable because their bodies are smaller and their immune systems are not yet fully developed. They will therefore suffer toxic reactions to mold at lower doses. If you or anyone in your household suffers from allergies or a suppressed immune system, you should have your home inspected by qualified mold professionals. An inspection may uncover a serious hidden mold problem and, even if it doesn’t, you’ll have peace of mind!

How can you get rid of orange mold?

If you notice small mold colonies in your home, you can usually tackle them yourself using proper equipment and procedures.

Before removing mold on your own, wear a respirator and protective gloves. This will prevent you from inhaling harmful mold spores and from developing any rashes on your skin from topical contact with mold.

Once you have protective equipment, wipe the affected area with a bleach or vinegar solution, leave it to soak (this gives the solution time to kill the mold), then wipe it away. Spray the area again to get any residual mold spores and leave it to dry.

orange mold on toilet
orange mold on toilet

Keep in mind that this DIY mold removal solution is effective only for surface mold growth, namely if the contaminated material is non-porous. If the material is porous (wood, drywall, etc.), it will likely require more in-depth cleaning.

If a mold infestation is larger than one square metre, Health Canada recommends that you hire reputable and experienced mold remediation professionals to remove the mold.

If you attempt to clean a mold infestation of this size yourself, you’ll likely make the problem worse by spreading spores to other areas of the home. You could also make yourself sick through exposure to massive amounts of mold.

Professional mold remediation is a good opportunity to have the cause of the mold infestation diagnosed so you can understand what caused the mold to grow in the first place in order to prevent it from growing back.


Most people are aware of only a couple types of mold, especially black and green mold. However, mold grows in all shapes, sizes and colours, so being aware of only a couple mold types makes you more likely to overlook potentially hazardous species growing in your home.

The more you learn about mold, the better your will be able to recognize mold infestations in your home and protect your health.

Published: February 20, 2019 Updated: April 10, 2020

John Ward

Written by:

Account Executive
Mold Busters

Fact checked by:

Mold Busters

Charles Leduc