How to Get Rid of Black Mold

The best way to get rid of black mold is to remove the mold, fix the moisture problem that caused it, and dry the area completely. Small areas of mold on hard surfaces can often be cleaned yourself. However, larger areas of mold, extensive water damage, contaminated water, or mold growing in porous materials such as drywall or carpet may require professional help.

And there is one important thing to understand before you grab your cleaning supplies: cleaning the mold is only part of the job. If you don’t find and fix the source of the moisture, the mold will probably come back.

I know how tempting it is to see a few black spots and immediately reach for the scrub brush. I have done the same thing. But over the years, I’ve learned that the most important question isn’t just “How do I clean this?” It is “Why is mold growing here in the first place?”

Can You Clean Black Mold Yourself?

Yes, you can often clean a small amount of mold yourself, particularly when it is growing on a hard, nonporous surface.

The U.S. Environmental Protection Agency (EPA) generally considers a moldy area of less than about 10 square feet, or roughly a 3-foot-by-3-foot area, small enough for most homeowners to handle themselves. Larger areas, extensive water damage, or suspected hidden mold can require professional help.

The type or color of the mold does not change the basic approach. You do not need to identify the exact species of mold before cleaning it. If you see or smell mold, the important steps are to remove it, correct the moisture problem, and dry the area.

What About Stachybotrys or “Toxic Black Mold”?

You may have heard the term “toxic black mold” used to describe Stachybotrys chartarum. This particular mold can grow in buildings when there is persistent moisture, but you cannot identify a mold species simply by looking at its color.

In other words, black-colored mold is not automatically Stachybotrys, and you generally don’t need a mold test just to determine what kind of mold you have before cleaning a small area.

Mold exposure can cause allergic reactions and respiratory symptoms in some people. People with asthma, chronic lung conditions, or weakened immune systems may be more vulnerable and should avoid cleaning mold themselves.

The Most Important Step: Find the Moisture

Mold needs moisture to grow. You can scrub away every visible spot of mold in your home, but if water continues to get into the area, the mold can return.

Before cleaning, look for the source of the moisture.

Check Under Sinks and Around Toilets

Look underneath bathroom and kitchen sinks, around toilet supply lines and bases, and anywhere plumbing could be leaking.

Don’t forget the walls and cabinets around these areas. A slow leak can go unnoticed for a surprisingly long time.

Check Around Appliances

Appliances that use or produce water can create mold problems when they leak.

Check:

• Behind refrigerators with water or ice dispensers
• Under refrigerators and other appliances
• Around washing machines
• Around dishwasher connections
• Around water heaters
• Around air-conditioning equipment

Inspect the Laundry Area

Check washing machine hoses and connections for leaks.

Your dryer should also vent properly to the outside. A dryer that releases warm, moist air into the home can add a significant amount of moisture to the surrounding area.

Check Windows and Air Conditioners

Condensation around windows can create enough moisture for mold to grow.

Window air-conditioning units deserve special attention because water can collect or drain improperly. Check the unit, surrounding wall, and floor for signs of moisture.

Look at the Roof and Gutters

Roof leaks are another common source of hidden moisture. Damaged shingles, flashing, skylights, clogged or damaged gutters, and storm damage can all allow water into parts of a home where mold can develop.

A musty smell can also be a clue that moisture or mold is present somewhere you cannot easily see.

Don’t Forget Behind Furniture

Furniture placed tightly against a cool exterior wall can trap moisture and restrict airflow. Check behind large pieces of furniture, especially in rooms that tend to be damp.

Closets, basements, garages and other areas with limited airflow deserve extra attention.

Fix the Moisture Problem Before Cleaning

Once you find the source of the moisture, fix it.

That might mean repairing a plumbing leak, fixing a roof, improving bathroom ventilation, repairing a window leak, replacing a damaged hose, or using a dehumidifier to control indoor humidity.

Cleaning mold without fixing the moisture problem is only a temporary solution.

EPA explains that moisture control is the key to controlling indoor mold. If you clean up mold but don’t fix the water problem, the mold is likely to return.

How to Clean Black Mold from Hard Surfaces

For a small amount of mold growing on a hard surface, the basic cleaning process is fairly simple:

1. Put on appropriate protective equipment.
2. Clean the moldy surface with detergent and water.
3. Scrub away visible mold.
4. Rinse the surface if necessary.
5. Dry the area completely.
6. Correct the moisture problem so the mold does not return.

EPA specifically recommends scrubbing mold from hard surfaces with detergent and water and then drying the surface completely.

You do not have to use an expensive “mold killer” to clean every small mold problem.

What You Need

For a small cleanup on a hard surface, gather:

• Rubber, nitrile or other protective gloves
• Goggles that provide good eye protection
• A sponge, cloth or appropriate scrub brush
• Household detergent
• Clean water
• Towels for drying
• A fan or dehumidifier if needed

Avoid touching moldy material with bare hands. CDC recommends gloves and appropriate eye protection during mold cleanup.

Cleaning the Mold

1. Put on your gloves and eye protection.
2. Apply detergent and water to the moldy surface.
3. Scrub the surface until the visible mold has been removed.
4. Rinse the surface when appropriate for the material.
5. Dry the area completely.
6. Dispose of or wash cleaning materials appropriately after the job.

Don’t be surprised if a dark stain remains after the mold has been removed. Mold can discolor materials, and cleaning does not always restore the original appearance. EPA notes that staining and cosmetic damage may remain even after mold has been cleaned.

What About Using Bleach on Black Mold?

Bleach is often the first thing people think of when they see mold.

CDC says that bleach can be used to clean mold from hard surfaces, using no more than 1 cup of household bleach per gallon of water.

However, the EPA does not recommend routine use of chlorine bleach or other biocides during mold cleanup. In most household situations, the goal is to physically remove the mold from the surface and eliminate the moisture that allows it to grow.

So I wouldn’t make bleach the first thing you reach for.

If you choose to use bleach, follow the product label and use it only on surfaces that are compatible with bleach. Ventilate the area, protect your skin and eyes, and never mix bleach with ammonia or any other cleaning product. Mixing bleach with other cleaners can produce dangerous fumes.

Can You Remove Black Mold from Drywall, Carpet and Other Porous Materials?

This is where mold cleanup gets more complicated.

Hard surfaces are generally much easier to clean because mold can be physically removed from the surface. Porous materials are different because mold can grow into their pores, spaces and crevices.

Drywall

If mold has affected drywall extensively, or the drywall has been heavily water damaged, simply wiping the surface may not be enough.

Hidden mold inside walls can also require professional evaluation and removal.

Carpet and Carpet Padding

Moldy carpet and padding can be difficult or impossible to clean completely because mold can penetrate the material.

If carpet or other absorbent materials have been soaked and cannot be dried quickly and thoroughly, replacement may be necessary.

Ceiling Tiles

Moldy ceiling tiles are another example of a porous material that may need to be discarded rather than simply cleaned.

Wood

Wood requires more care because it can absorb moisture. Whether it can be successfully cleaned depends on the type and condition of the wood and how deeply the mold has affected it.

If you are unsure whether an item can be safely cleaned, especially if it is expensive or has sentimental value, consider consulting a specialist.

Don’t Just Paint Over Black Mold

It can be tempting to clean up a moldy wall as best you can and then cover the whole thing with a fresh coat of paint.

Don’t.

Clean the mold and dry the surface before painting. Paint applied over a moldy surface is likely to peel, and painting does not solve the moisture problem that caused the mold.

If a cleaned surface remains stained after the mold has been removed and the material is completely dry, a suitable stain-blocking primer may help with the appearance. But primer and paint should never be used as a substitute for mold removal and moisture control.

What About Vinegar, Borax and Other Home Remedies?

You’ll find plenty of recipes online using vinegar, borax, baking soda and other household products for mold.

I’m not going to tell you that you need a complicated homemade recipe to deal with a small patch of mold.

For ordinary mold cleanup on hard surfaces, detergent and water is the simple starting point recommended by EPA.

If you decide to use a commercial mold-cleaning product or another cleaning chemical, read the label and follow the manufacturer’s directions.

And remember the golden rule of cleaning:

Never mix cleaning products.

Using more than one cleaner does not necessarily mean you’re going to get a cleaner surface. In some cases, mixing products can create dangerous chemical reactions.

How to Prevent Black Mold from Coming Back

Once the mold is gone, your next job is keeping the area dry.

Control Indoor Humidity

EPA recommends keeping indoor humidity between 30% and 60% to help reduce mold growth. Air conditioners and dehumidifiers can help control excess moisture.

A small inexpensive hygrometer can help you keep an eye on humidity levels.

Use Bathroom Exhaust Fans

Run bathroom exhaust fans when showering and for a while afterward. Ideally, exhaust fans should vent outdoors rather than simply moving moist air into another part of the house.

Keep the Dryer Vented Outside

Make sure your clothes dryer vents properly to the outside. Never intentionally vent a dryer into an attic, crawlspace, garage or other enclosed area.

Dry Wet Areas Quickly

If something gets wet, dry it as soon as possible.

After significant water damage, CDC recommends cleaning and drying affected areas quickly. Wet materials that cannot be thoroughly dried may need to be removed.

Improve Air Circulation

Don’t pack belongings tightly against walls, particularly exterior walls in damp rooms.

Leave enough space for air to circulate around furniture and other large objects.

This is especially helpful in closets, basements, garages and other areas where air tends to become stagnant.

When Should You Call a Professional for Black Mold?

Not every mold problem is a DIY cleaning job.

Consider calling a professional when:

• The mold covers more than about 10 square feet.
• There has been extensive water damage.
• Mold is growing inside walls, ceilings or other hidden areas.
• Large amounts of drywall, insulation, carpet or other porous materials are affected.
• The water involved sewage or other contaminated water.
• The mold continues to return after the moisture problem has been corrected.
• You cannot find the source of the moisture.
• The cleanup would require extensive removal of moldy building materials.
• You have health concerns that make it unwise for you to perform the cleanup yourself.

EPA recommends considering professional help when mold covers more than about 10 square feet or when there has been significant water damage. Contaminated water, such as sewage, is another situation where professional assistance is appropriate.

If you suspect mold is growing inside a wall, ceiling or another inaccessible area, don’t start tearing into the building materials just to see what is behind them. A qualified professional can determine how extensive the problem is and how it should be handled.

Frequently Asked Questions About Black Mold

What is the fastest way to get rid of black mold?

The fastest solution is not simply spraying the mold with a chemical. For a small area on a hard surface, physically remove the mold with detergent and water, dry the area completely, and correct the moisture problem that caused it.

Does bleach kill black mold?

Bleach can kill mold on appropriate hard surfaces, but EPA does not recommend routine use of bleach or other biocides for mold cleanup. Removing the mold and correcting the moisture problem are the important steps.

Does vinegar kill black mold?

Vinegar is commonly suggested as a homemade mold cleaner, but you do not need vinegar to clean a small mold problem. EPA recommends detergent and water for removing mold from hard surfaces.

Why does black mold keep coming back?

The most common reason is continued moisture. A leak, condensation, high humidity, poor ventilation or hidden water damage can continue feeding the mold even after the visible growth has been cleaned.

Can black mold grow behind walls?

Yes. Mold can grow in hidden areas when moisture gets inside walls, ceilings or other building materials. If you suspect hidden mold, professional evaluation may be appropriate.

Do I need to test black mold?

Usually not. You don’t need to know the type of mold before cleaning a small visible area. CDC recommends removing mold and fixing the moisture problem rather than focusing on identifying the type.

Is black mold dangerous?

Mold exposure can cause allergic reactions and respiratory symptoms in some people. People with asthma, chronic lung conditions or weakened immune systems can be more vulnerable to mold exposure.

The color of the mold alone does not tell you how dangerous it is or what species it is.

Can I paint over black mold?

No. Mold should be cleaned and the surface completely dried before painting. Painting over mold does not solve the underlying problem, and paint applied over moldy surfaces is likely to peel.

Getting Rid of Black Mold

Getting rid of black mold isn’t just about finding the strongest cleaning product you can buy. Remove the mold, fix the moisture problem, and dry the area completely.

For a small patch of mold on a hard surface, you can often handle the cleaning yourself with basic cleaning supplies, detergent and water. Larger mold problems, extensive water damage, contaminated water, hidden mold and extensive growth on porous materials are better left to professionals.

And remember, if you clean the mold but don’t fix the water problem, you haven’t really solved the problem. The moisture is what allowed the mold to grow in the first place.

So before you reach for the scrub brush, grab a flashlight too. Sometimes the most important part of cleaning up black mold is finding the water hiding behind it.

References

CDC – Mold Overview

EPA – Mold Cleanup in the Home

EPA – Basic of Mold Cleanup

Household Cleaners