Posted on: March 31, 2023

Identifying Mold Types: What Colors are Mold and Mildew?

How to Identify Different Molds

You've found basement mold, and it's black, or maybe green. Or is that more like gray?

You know black mold is harmful. But is it worse than green mold? Could it be mildew? Is mildew safer than mold?

How can you tell what kind of fungus have in your home and how dangerous it is?

What Colors Are Mold?

House fungus comes in all the colors of the rainbow. Black, greenish, or gray mold is common, but it can also appear brown, purple, white, orange, yellow, pink, red, or a mixture.

When it comes to identifying mold types, the color of the mold in your home won't tell you anything. No matter what you'll read about white mold vs. black mold vs. green mold, the color itself won’t be able to tell you the type, severity, or health risks you could potentially face. 

What Affects Mold Color?

Mold color is affected by age and conditions like food source, humidity level, and the amount of light. In other words, the same patch of mold can change colors as it matures or as the environmental conditions change.

What's the Difference Between Mold and Mildew?

The main difference between mold and mildew is that mildew grows along a surface without penetrating it, making it much easier to clean and remove.

Mold problems go a lot deeper, sending hyphae into the material where it's growing. As a result, you may need to remove carpet, drywall, and other porous materials to resolve the issue.

Not only is a mold problem harder to resolve than a mildew problem, it's also more dangerous to your health. You're at risk of inhaling spores and any fungal toxins present, resulting in acute and long-term effects.

What is Black Mold?

Several types of mold in homes can be black, but when people say "black mold," they're talking about a kind called Stachybotrys chartarum. It's often found as basement mold but can grow in any damp environment, including bathrooms, kitchens, and areas around leaking pipes.

Why is Black Mold So Dangerous?

Many different types of mold, mildew, and fungus can cause respiratory symptoms, including allergic reactions, shortness of breath, coughing, wheezing, sore throat, edema, or lung bleeding.

However, black mold is considered particularly dangerous – often called "toxic mold" – because it produces neurotoxic compounds that can kill brain cells. Children and immunocompromised people are especially vulnerable to neurogenic mold problems.

The neurological symptoms of toxic mold include confusion, brain fog, dizziness, memory loss, anxiety, and even seizures. Neuron toxicity can cause other problems, including heart palpitations, vision impairment, etc.

What Does Black Mold Look Like?

You'll often smell black mold long before you see it since it often starts growing inside the wall. Stachybotrys has a musty, earthy scent. When you see mold growth on the surface, it's usually an already established and severe problem.

"Black mold" isn't only black but typically dark in color, including greenish-black, gray, or brown. It grows in a spotty, irregular pattern with a color variation indicating age (including spots or specs of lighter color). However, the spore groupings may grow together, leaving something resembling a black stain.

It's usually slimy, but younger growth can appear powdery, and older growth can appear furry.

Black mold likes material with a high amount of cellulose, including carpet, paper, fiberboard, sealant, and grout. As black mold eats through a surface, the material grows rotten and brittle over time. The ability to cause structural damage is another reason black mold is so notorious among homeowners.

How Do You Identify Black Mold vs. Mildew?

Mildew isn't as pungent in scent, and it looks more fluffy or powdery (but black mold, when cut off from its source of moisture, can take on a mildewy texture).

House mildew is often also lighter in color, which is why you'll hear people talk about white mold vs. black mold in terms of good and bad. However, some types of mildew can resemble black mold. For example, Cladosporium is often a dark green with a spotty growth pattern.

It's challenging to identify mold types accurately by any aspect of sight or scent. Everything we've mentioned in this article – color, texture, growth pattern, location, and other characteristics – are general rules of thumb for identifying mold types. Various colors and textures can occur in multiple species. Even mold test kits will only confirm fungal growth rather than identifying the mold type.

Only a certified mold inspector can provide definitive house fungus identification if you suspect a black mold problem. They're also your best bet for evaluating the extent of the problem and how to resolve your mold problem permanently.

How Do You Hire a Certified Mold Inspection and Removal Specialist?

You might ask your homeowner's insurance if they have any recommended or preferred vendors in your area. Even if they can't give you names of specific businesses, they may be able to tell you what kind of certification or credentialing they accept – like certification from the National Association of Mold Professionals (NAMP).

Some jurisdictions require special licensing for professionals that deal with mold in homes, so learn about local laws and regulations to ensure that you meet them.

Once you know legal and insurance requirements, you'll want to collect quotes and compare prices. But remember, just like any home contractor, the cheapest option might not be the best option. Check for reviews and reputations and interview companies for professionalism.