How to Get Rid of Mold on Walls

Finding mold inside or on walls of a property is an often dangerous and frustrating issue. It requires swift action as soon as it is noticed due to the health problems and aesthetic damage it can cause to a home. It is also important to first understand the difference between mold and mildew.

Is It Mold or Mildew?

The most common reason both fungi develop on walls are condensation, humidity, or water leaks. Both mold and mildew thrive in humidity or areas with poor ventilation.

Mostly found on flat surfaces in areas with a lot of moisture, mildew is a gray or white colored powdery substance. The good news is, because mildew is a surface mold, it doesn’t typically cause damage to a property’s structure.

On the contrary, mold can cause structural problems and health issues because it is a fungus that spreads via airborne spores. Mold is typically black, yellow, or green with a fuzzy or slimy look and feel.

Signs of Mold on Walls

Mold most commonly grows along interior walls or near ceilings, floors, and along baseboard trims. While it can attack kitchens, laundry rooms, basements, or any other poorly ventilated area, mold is most often a problem in bathrooms.

Tell-tale signs that a home has a mold infestation are:

  • A damp or musty odor
  • Paint that begins to crack or peel
  • Visible growth on interior walls and ceilings
  • People developing allergy symptoms indoors

Even if you discover only a small amount of mold growing in your home it is important to act quickly to remove it. This will hopefully avoid it spreading and causing health issues or property damage.

Many studies done have found that mold exposure is often the cause of allergic reactions or poor health. Symptoms such as a runny nose, irritated eyes, or breathing difficulties being the most common.

How to Get Rid of Mold on Walls

Mold is easy to get rid of when it covers only a small area. Try using household products like hydrogen peroxide, borax, bleach, vinegar, tea tree oil, or baking soda.

Unfortunately, mold that has spread on walls and covers a significant area is much more difficult to remove and has potential to be hazardous, so it’s best to reach out to a professional mold removal service to rid your home of dangerous mold in a safe and effective way.

Keep In Mind

According to the Environmental Protection Authority, if the area covered in mold is less than ten square feet it can be done without the aid of a professional.

To do it yourself, you’ll need to complete two steps: controlling the moisture in your home and killing the mold.

Identify the Cause of the Mold

Identification of the root cause of the mold is the most important step of the entire process to ensure that the issue does not reoccur.

By repairing the source of any water damage or leaks, you should be able to better control the moisture of your home.

Prepare Your Room and Clean the Walls

Before starting to remove the mold itself, you must clear out the affected area and remove furniture, fabrics, and all electrical equipment and then cover your flooring with protective plastic sheets.

Before getting close to the moldy area, it’s important to protect yourself by wearing safety glasses, rubber gloves, and a mask to avoid direct exposure to the area. It also helps to open windows and doors, if possible, to air out the room. Finally, remove any dirt and clean the affected area with a damp sponge and liquid dishwashing soap.

Mold Removal

Moldy patches found on interior walls that have been painted or sealed mean that the mold is most likely only on a surface level which is usually easy to get rid of with common household cleaning products like borax, white vinegar, baking soda, or tea tree oil.

We recommend that you attempt using a natural mold remover first if the moldy patches cover only a small area of a painted or sealed wall.

When you have a bigger area of mold and natural removers are inefficient, we recommend a slightly stronger chemical-based cleaner that can be found online or at a home improvement store.

When dealing with an unsealed or porous wall such as cement, concrete, or stone, the mold tends to grow on the outside and inside of the wall, so we recommend using a combination of hydrogen peroxide and white vinegar.


In a large bowl or container, place one cup of borax with a gallon of hot water and stir, making sure to stir or shake well to ensure the dissolution of the borax. Transfer the mixture to a spray bottle and spray on the moldy area.

Do not rinse off the solution—simply scrub the mold on the wall with a brush and wipe clean, allowing it to dry completely. If you have indeed controlled the source of the mold, the borax in the mixture will aid in preventing any mold from reoccurring.

Vinegar and Baking Soda

On both porous walls and non-porous walls, vinegar is a safe and effective solution to kill mold and prevent it from returning. By killing the mold at the source, many studies claim that white vinegar is effective at killing up to 82% of mold spores.

Without diluting it, pour white vinegar into a spray bottle and apply it to the affected wall. Leave it to soak for an hour before wiping it with warm water and a sponge.

You may need to scrub the moldy area after cleaning with vinegar, so we recommend using a baking soda solution.

A natural disinfectant, baking soda can be very effective at killing mold. This has other functions, like killing odors to remove the damp, musty smell mold brings and absorbing moisture to keep future mold at bay.

To create the mixture, combine one teaspoon of baking soda with two cups of water and transfer to a spray bottle, shaking well. Spray the solution onto the moldy area and use a sponge or brush to scrub the area.

Finally, use warm water to rinse the affected area and spray the vinegar or baking soda mixtures onto the wall one more time to keep any other mold from growing.

Tea Tree Oil

An essential oil, tea tree is naturally anti-fungal and antibacterial. This makes it an effective solution for ridding your walls of mold. Mix one teaspoon of tea tree oil with two cups of water and transfer to a spray bottle. Then apply the mixture onto the moldy spots and wipe the area clean with a cloth.

With tea tree oil, there’s no rinsing required because leaving it on the affected surface will stop the mold from reoccurring. The tea tree oil solution works best on painted or wallpapered surfaces.

Grapefruit Seed Extract

Grapefruit seed oil is also a natural mold killer. The citric acid in grapefruit seed oil effectively attacks mold and kills it while simultaneously disinfecting and ridding the area of odors.

Using ten drops of grapefruit seed oil per one cup of water, create the solution and transfer into a spray bottle, shaking well. Spray the mold with the solution and wipe the area with a clean cloth.

By not rinsing the solution and leaving it on the wall, it will keep the mold from coming back. We recommend using this method every two or three days for maximum prevention.


Bleach, which works best on painted or sealed walls, has potential to damage the finish on your surface. It’s important to perform a test on a small patch of wall that will not be noticeable.

Mix one part bleach with three parts water and apply the mixture to the moldy area, letting it soak for ten minutes. Then scrub the area with a brush before rinsing and drying it with a cloth.


Prior to using the bleach method, be sure to open windows and doors for proper ventilation and put on a safety mask to avoid inhaling toxic fumes.

Hydrogen Peroxide and Vinegar

Hydrogen peroxide is a great solution for pesky mold and becomes even more effective when used with white vinegar. It is antifungal, antiviral, and antibacterial. This solution, as opposed to bleach, is non-toxic and can kill mold on both porous and non-porous surfaces.

After pouring 3% concentration hydrogen peroxide into a spray bottle, apply it to the mold, let the solution soak for ten to 15 minutes, and scrub with a sponge or brush.

Types of Walls

Depending on the type of wall the mold is growing on, the best technique for removal may vary.

Drywall: Due to its porous nature, mold on drywall will often grow on the surface as well as inside the wall so it’s best to use the vinegar solution rather than bleach. Unfortunately, if the mold reoccurs, typically the best solution is just to get new, mold-resistant drywall and replace the existing material.

Concrete: We recommend scrubbing with a vinegar or hydrogen peroxide solutions on brick or concrete because they are porous and will need the mold to be killed at the root.

Cinder Blocks: Cleaning the wall first, choose any solution and scrub the cinder blocks with a brush, wiping any mold residue and reapplying the solution. Allow this to soak for up to 20 minutes and make sure it dries.

Wallpaper: Tea tree oil, grapefruit seed oil, or vinegar are the most effective solutions on wallpapered areas. After performing a test in an unnoticeable area, use a sponge and a small amount of your chosen solution to remove mold. Be sure to avoid getting the wallpaper too wet.

Tips for Preventing Mold on Walls:

By controlling the moisture and humidity in your home by utilizing a dehumidifier and making sure all areas are properly ventilated, you should be able to prevent any mold or mildew growth on your walls.

By properly insulating your roof, windows, exterior walls, and pipes, you can avoid condensation which can often be the root cause of mold.

It is also important to regularly clean bathrooms and kitchen areas to prevent mold from growing in these highly susceptible areas.

Hiring a Mold Removal Expert

If you find that you have a significant amount of mold in your home, the EPA recommends that you hire a certified, insured, and trained professional that specializes in mold removal to perform the job.

A professional trained specifically in mold removal will start by taking samples of the mold in your home to test it to identify the type. Following the identification, they will likely form a plan to remove and prevent any future mold.

They will then perform the removal process before performing tests and giving you a clearance report.

Clean Walls, Clean Home

Act immediately if you notice mold in your home to prevent the spread and avoid health issues and property damage.

Most importantly, you must find and remedy the source of the mold to prevent it from returning. From there, you can remove the mold yourself or hire a professional, depending on the size of the affected area.

If you opt to do it yourself, the process is rather easy and can be done with common products like borax, vinegar, baking soda, tea tree oil, bleach, or hydrogen peroxide, however, we recommend calling in a professional if the mold is significant.

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.