How to Get Rid of Mold on Walls
Tips & Tricks

How to Get Rid of Mold on Walls

It’s pretty easy to tell if you have a mold problem in your home. You will see a distinct black, yellow, or green patch on your walls, cracked and peeling paint or wallpaper, or a musty odor in the room.

Mold on walls is quite unsightly, can cause structural issues, and is a health hazard. That’s why it’s important to remove it immediately, even if it’s a small patch. Unfortunately, regular household detergent is not powerful enough to remove mold completely.

As long as the mold is on the surface, it is generally easy to remove yourself. The best mold remover for walls includes borax, hydrogen peroxide, baking soda, bleach, vinegar, and tea tree oil.

After getting rid of the mold, control the moisture levels in your home to prevent a recurring mold issue. Read further to learn more about what causes mold to grow on walls, how to remove them permanently, and preventive measures to keep your walls mold-free.

What causes mold on walls?

Mold will grow and thrive in places conducive to its survival. And three things promote the growth of mold on walls they include;


Whether the source of moisture is humid weather, condensation, or water leaks, mold growth is inevitable. Most mold species require at least 70% of relative humidity to thrive. So limiting moisture and removing active mold colonies is the best way to get rid of mold.

There are a variety of mold species. But black mold on walls is one of the more stubborn types found in homes. Black mold requires constant moisture. Therefore, you will likely see it in areas with severe water damage.


Mold varieties tend to grow in a wide range of temperatures. Even low temperatures close to freezing will not inhibit mold growth. However, mold thrives better in warmer environments. Rooms with poor air circulation have the right temperature to promote any mold spores in the air to grow.


Mold feeds on things that contain carbon atoms like organic substances, Most materials used to build walls will provide suitable food for molds, such as timber and paper.

If all these three conditions are present, you are likely to have mold growing on your walls and other surfaces.

How to get rid of mold on walls permanently

Even though mold is a health hazard, you don’t need to hire a professional to remove mold. Instead, you should hire professional mold removers if it’s a significantly large area of more than 10 square feet (3 square meters). So follow the guide below on how to get rid of mold permanently and some natural mold treatments for mold remediation.

Things you’ll need

  • Protective gear
  • Spray bottle
  • Scrubbing brush
  • Clean, dry rags
  • Detergent
  • Mold killing products: bleach, borax, vinegar, ammonia, hydrogen peroxide,  baking soda, or tea tree oil


Identify the cause of the mold growth

Identifying and tacking the source of the issue is the most important step in ensuring the mold doesn’t grow back after cleaning. Check your house for water damage such as leaking pipes or faucets and have a professional plumber fix it.


You need to prepare the room and wall before cleaning the mold to avoid spreading the mold all over your furniture. Here’s how to prepare before removing mold from your walls;

  • Remove furniture and electrical appliances from the room and cover the floors with plastic sheets.
  • You should also wear protective gear such as safety glasses, rubber gloves, and a respirator to protect you from the mold. In addition, if you have sensitive skin, it’s important to wear work overalls to prevent skin contact with mold spores.
  • Wipe the moldy walls with a damp cloth to remove dust and dirt.
  • Open the doors and windows to promote ventilation.

Removing the mold

Mold growing on the surface will look like small spots and are easier to clean using household products. But larger mold patches indicate they have penetrated deeper into the wall and will require professional mold removers.


Borax(sodium tetraborate) is a natural cleaning product that can kill mold spores due to its high alkalinity of pH 9.3.

How to kill mold with borax

  • Mix one cup of borax with a gallon of hot water in a bucket.
  • Stir the mixture well to dissolve the borax.
  • Fill the spray bottle with the borax solution and spray the moldy surface.
  • Then use a nylon brush to scrub the mold off the wall.
  • Wipe the wall with a clean, dry rag and allow it to dry. You will not have to rinse the solution.


Another method is to use vinegar to kill mold. White vinegar kills about 82% of mold species growing on both porous and non-porous walls due to its disinfecting properties. It is also a natural deodorizer that won’t corrode your walls. Undiluted distilled vinegar will also help eliminate white mold on wooden walls.

How to kill mold with vinegar

  • Fill a spray bottle with distilled vinegar without diluting it.
  • Spray it on the wall and leave it for an hour.
  • Then wipe the area with a cloth and warm water.
  • Repeat this process every few days to keep the wall mold-free.

Baking soda

Baking soda is a natural disinfectant and deodorizer. It will kill the mold while also removing the musty smell from the moldy wall.

How to kill mold with baking soda

  • Mix one teaspoon of baking soda with two cups of warm water in a spray bottle and shake until the baking soda dissolves. Spray the moldy wall with the solution and use a nylon-bristled scrubbing brush.
  • Rinse the wall with warm water to remove residual mold from the surface.
  • Lastly, spray either white vinegar or baking soda solution to kill any remaining mold while deodorizing the room.

Tea tree oil

Tea tree essential oil effectively tackles mold due to its anti-fungal and antibacterial properties. Although pricey, it is also effective at removing mold on painted and wallpapered walls. Tea tree oil is also a natural product that will remove mold from painted walls.

How to kill mold with tea tree oil

Fill a spray bottle with two cups of warm water and add one teaspoon of the tea tree oil.

Spray the mixture onto the mold patches and wipe off with a clean cloth. This method requires no rinsing.


Bleach is excellent at cleaning mold on on-porous walls. It will also remove any mold stain from your white walls. Unfortunately, bleach cannot penetrate porous walls and kill the mold from the roots. That means it will not remove the mold permanently. It’s also important to do a patch test of the bleach to ensure it doesn’t damage your finish.

How to kill mold with bleach

  • Open the windows for air circulation and wear gloves, safety goggles, and a respirator mask. It produces toxic fumes that can irritate your respiratory tract.
  • Mix one part bleach and three parts water in a spray bottle.
  • Spray the mixture on the mold and leave it for 10 minutes.
  • Then scrub off the mold with a nylon-bristled brush.
  • Rinse with clean water and dry the area with a clean cloth.

Hydrogen peroxide and vinegar

Hydrogen peroxide is a great alternative to using bleach to kill mold because it doesn’t produce toxic fumes and it’s environmentally friendly. It is also antiviral, anti-fungal, and antibacterial.

How to kill mold with hydrogen peroxide and vinegar

  • Pour 3% hydrogen peroxide into a spray bottle.
  • Spray the moldy wall until it is completely saturated, then leave it for about 10 minutes.
  • Scrub the area with a brush to clean mold off the walls.
  • Finally, wipe down the surface with a clean, dry cloth to remove any residue. This method requires no rinse.

How to prevent mold from growing on your walls

The best way to permanently tackle mold on the wall is to control moisture in your home. That’s because mold thrives in high humidity areas. There are several sure ways you can reduce the humidity in your home; they include;

  • Keep your home’s humidity levels under 50% all day long by installing a reverse cycle air conditioner or dehumidifier. You can also purchase a hygrometer that measures your home’s humidity and alert you when humidity levels are too high.
  • Clean and maintain your roof gutters regularly.
  • Increase your home’s ventilation to allow air to move freely in and out of the house. You can use exhaust fans, especially in rooms with high humidity, such as the kitchen and bathroom. Also, make sure your clothes dryer vents outside your home.
  • Consult a professional plumber to inspect your home’s water system and fix any leaks to prevent mold from growing.
  • If you’ve experienced a flood, it is best to dry everything wet completely. Do not also leave wet items such as towels around the house.
  • After a bath, turn on a ventilation fan or open a bathroom window to reduce humidity.
  • Use mold inhibiting paints to paint your walls. These paints will effectively inhibit mold growth on painted surfaces. There are also mold-killing primers with anti-fungal properties that can kill all mold, mildew, and other fungi growing on walls.
  • Use a vacuum cleaner with a HEPA (high-efficiency particulate air) filter to clean your home daily. It will clean off mold spores from your carpet and furniture.
  • Clean carpets if you notice a musty odor in the carpeted rooms, and make sure they dry completely before taking them back into the house. Also, get them professionally cleaned once a year to ensure they don’t grow mold.
  • Clean your bathroom weekly with any mold-removing products earlier mentioned or commercial surface mold cleaner. Regularly cleaning your bathroom walls will also keep mold growth at bay.
  • Check the ground around your home and ensure it is sloped sufficiently away from the foundation. Often the land can slope towards your foundation and accumulate water there. This water can penetrate your basement and, over time, promote the growth of mold on the walls.
  • Remove mold from your house plants. Moist soil in indoor plants is an excellent breeding ground for mold, which can easily spread to your walls. Instead, you can keep your plants outdoors or on the balcony or pour some Taheebo tea into the water you give your houseplants. This tea hinders mold growth in plant soil, and you can find its natural food stores.

What happens if you don’t get rid of mold growing on your walls?

A small patch of mold growing on your wall may seem harmless, but this fungus spreads fast. It matures quickly and produces spores. These spores get into the area and can spread all over your home and wreaking havoc in no time. Here’s what will happen if you don’t tackle the mold problem in your home;

Health hazard

Research shows that mold can cause allergic reactions and other health issues. Even short-term mold exposure can have allergic reactions presenting as running nose, eye and skin irritation, and breathing difficulties. Mold can be fatal to certain people such as infants, older adults, people on chemo, people with severe asthma, and other respiratory issues.

Similarly, mold can also affect your pets and cause serious breathing complications. So ultimately, not killing the mold will cost you a lot of unnecessary medical expenses.

Stains and discoloration

One of the initial signs of mold growth is water stains on the very unsightly walls. Mold usually appears in various black, white, green, blue, or yellow shades. The black mold is most common on walls with excess water damage.

Without dealing with the source of the mold issue, the mold overgrows and discolors the walls permanently, indicating the moisture damage is from within the walls. Eventually, you will spend money repairing and repainting the walls.

Deteriorates the walls

Certain mold types will affect the structural integrity of your walls if not managed properly. Over time, the paint and wallpaper can bubble, crack and peel. If it goes untreated for longer, the mold will start feeding on the wood, making it rot, and eventually, the walls come down. This will also cost you unnecessary expenses spent on repairing weak walls.

Musty smell

Mold gives off a very musty odor that is not easy to ignore. This odor can be a great issue for people with respiratory issues such as asthma, lung disease, or people with compromised immune systems. Unfortunately, no amount of deodorizing will helps unless you fix the issue causing the mold and then kill the mold with an effective product.


Mold can grow into bigger colonies as long as the area is hospitable. That’s why the best way to kill mold permanently is by fixing the source of high humidity in your home. Then you can use vinegar, baking soda, tea tree oil, bleach, hydrogen peroxide, or borax to get rid of the mold growing on your walls. All these products effectively kill mold from the roots to prevent regrowth while also deodorizing the affected room.