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How to Remove Mold from Walls

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Follow your nose to find the source of that musty, unpleasant smell, and it will most likely lead you to mold. Mold thrives in dark spaces that have poor ventilation like closets and basements.  The best way to deal with mold, like any other problem, is to prevent it from starting in the first place. 

But alas, what is life without a little mold in it? If you already have mold, it is time to declare war, ASAP. It is you against the mold, but luckily, I am on your side, and I am going to explain exactly how to remove mold from your walls.

Removing mold from walls is pretty easy if you have caught it in time. This is why your sense of smell is your first line of defense. A musty smell is almost always the first sign that mold is growing somewhere. Your nose knows. And once you have identified the location of the mold, you must do two things. Destroy that mold, and then determine the cause so that it doesn’t happen again. I am going to explain how to do this in a few easy steps with common household products.

Why, mold? Why did you come into my life?

“There is a fungus among us”. I wonder if Terry Noland ever had to deal with mold on his walls. Mold is a fungus that develops in dark and humid conditions. It could develop from water damage caused by a burst or leaking pipe, poor ventilation, or in a room with high humidity like in a bathroom. Mold can also develop when there is condensation. Condensation occurs around windows and doors that are poorly insulated. When the temperature outside the home is different from the temperature inside the home, little beads of moisture form.

The first sign of mold is a musty odor. But as the mold spreads, there will be visual signs: peeling or bubbling paint and visible mold spores that are usually green, yellow, or black. Other signs are allergy symptoms like coughing, sneezing, and trouble breathing.

Mold is quite damaging to your home’s structure and furniture as well as to your personal belongings. More importantly, it is dangerous for your health. Other than causing allergy problems, it can lead to depression and anxiety, hair loss, and weight gain, to name a few. And I don’t know about you, but I would prefer my weight gain to come from decadent desserts rather than toxic mold spores.

Walls are porous, meaning they absorb materials. Some walls are more porous than others but all walls, regardless of whether they are drywall, concrete, cement, or stone will absorb mold. Paint and plaster are porous as well. This is another reason to act fast. With time, the mold will spread beyond the surface of your wall making it more difficult, if not impossible, to remove.

Kill that mold!

The first thing you have to do is assess the affected area of the mold. Ask yourself this question. How large is the affected area? If it is greater than 10 square feet, it may be time to call in a professional mold removal service. Anything less than this, you can tackle by yourself easily and quickly.

The battle has begun! But like any other battle, you would not go into it without protective gear, right? You definitely don’t want to take the mold off your walls only to have it end up in your eyes, mouth, or on your hands. I highly recommend that you wear protective goggles, gloves, and a mask to keep yourself safe.

You also want to protect your furniture, fabrics, and floors. Start by removing all the items from the area. When it is all clear, lay down a protective sheet/tarp on your floor.

First things first; clean the area

Before you get to the root of the mold, you will first need to clean the area of dirt and dust. Using dish detergent and a damp sponge, wipe the wall with a circular motion, continuously rinsing out the sponge and repeating. 

Household and natural cleaning products

I always prefer using natural household products when I can. They are cheap, accessible, and safe. They are also very effective in removing mold.

White vinegar

Natural, safe, and probably sitting in one of your cabinets right now, vinegar is a very effective mold remover. White vinegar has been shown to kill most mold species including the dreaded black mold. Don’t dilute it as this will make it less effective.

  •         Pour the vinegar into a spray bottle.
  •         Spray on the affected area. Be generous.
  •         Leave on for 1 hour.
  •         Wipe with a damp cloth.

Don’t worry about the smell. I know the smell is not much better than the mold, but that will disappear after a few hours. If you haven’t got white vinegar at home, apple cider vinegar has been shown to be equally effective. Another tip,  vinegar can also be quite helpful in removing mold from your washable fabrics and clothing. Simply toss some vinegar into your washing machine’s detergent compartment. I like to run vinegar through my washing machine about twice a year anyway to give it a thorough cleaning.

Baking soda

Baking soda is great for absorbing moisture and odors. My mom used to keep an open box of it on the door of the fridge to prevent odors. It really has a multitude of uses and removal of mold is one of them.

  •         In a spray bottle, combine 1/4 tbsp. of baking soda with 2 cups of water.
  •         Shake well and spray onto the affected area.
  •         Scrub immediately with a brush.
  •         Rinse with water.
  •         Spray again and let dry without rinsing with water.
Vinegar and baking soda paste

 For really stubborn mold, you can try combining vinegar and baking soda (with a little water) and making this paste:

  •         Combine 2-parts baking soda with 1-part vinegar and 1-part water.
  •         Mix until you have the consistency of a paste.
  •         Apply to the affected area and let dry for several hours.
  •         Scrape away.
  •         Wipe down with a damp cloth.

Tea tree oil

Essential oils are plant extracts. They are known for their many benefits for our health. Tea tree oil is antimicrobial and antifungal making it highly effective in mold removal. What’s more is that once it has killed the mold, it can stop it from coming back as well. It should be diluted with water. Always use protective gloves when using this. Even though it is natural, it is highly concentrated and can irritate your skin.

  •         In a spray bottle, mix 1 tsp. of tea tree oil with 1 cup of water.
  •         Shake well.
  •         Spray on the affected area.
  •         Let dry for 1 hour.
  •         Wipe down with a dry cloth.

Hydrogen peroxide

Anti-fungal, antiviral, and antibacterial, hydrogen peroxide is wonderful for mold removal. Even professionals use hydrogen peroxide-based cleaners. Use a 3% concentration.

  •         Pour into a spray bottle.
  •         Leave on for 10 minutes.
  •         Scrub the area with a brush.

You can even add a little vinegar to the mixture to improve its effectiveness.

Borax

Borax or sodium borate is a type of salt– not edible– found in many laundry detergents, household cleaners, and even in some cosmetics. Now banned for this purpose in the US, it was once used as a food preservative because of its antifungal properties.

  •         In a spray bottle, combine 1 cup of Borax with 1 gallon of hot water.
  •         Shake well.
  •         Spray onto the affected area.
  •         Scrub immediately with a brush.
  •         Wipe the area clean and let it dry.

Lemons

I am a huge fan of using lemons as a natural stain remover. If you have ever gotten a food stain on a lovely white shirt, you can use lemon juice instead of bleach to treat the stain. Lemons are great for removing mold. The acid in the lemon breaks down the mold. As a bonus, who can resist that fresh smell?

  •         Juice 3-5 lemons.
  •         Apply to the area.
  •         Let it sit for 5 minutes.
  •         Wipe the area down with a damp cloth.

Bleach

I am not a huge fan of bleach for removing mold from walls though many professionals use bleach-based products for this purpose. Bleach cannot penetrate walls and kill mold below the surface. That’s why, even if it looks like the mold is gone, it will most surely come back again. Bleach is, however, very effective on nonporous surfaces like glass and ceramic tile. For this reason, I do recommend using bleach for the removal of mold on surfaces in the bathroom.

  •         In a spray bottle, combine 1 cup of bleach with 1 gallon of water.
  •         Apply to the affected area.
  •         Let it sit for 1 hour.
  •         Wipe down with a damp cloth.
  •         Spray again and let dry without wiping down to prevent mold regrowth.

Always ventilate the room when working with bleach to avoid inhaling its toxic fumes. Also, as I always mention in most of my articles, never mix bleach with vinegar as this will create a dangerous toxic gas.

Once the mold has been removed from walls with one of the other methods I describe above, bleach can be useful in removing any remaining stains. Just remember again that if vinegar was your method of choice, you will want to avoid putting bleach on the same area. 

Store-bought products

If you prefer store-bought concoctions, there are many on the market. Store-bought products have the advantage of being ready to use. No need for preparation. On the downside, they are not everyday products found in one’s home and are more expensive. Also, they are not always safe and eco-friendly. Check out these three on amazon:

Concrobium Mold Control

This is an excellent chemical product that professionals use to tackle mold. The active ingredient, sodium carbonate, breaks apart the mold spores. It also claims to prevent mold regrowth. It is a registered product with the Environmental Protection Agency. It is very easy to use and it comes in a spray bottle for easy application.

  •         Apply to the affected area.
  •         Let dry.
  •         No need to scrub or rinse.

RMR-141 Disinfectant and Cleaner

This product is also registered with the Environmental Protection Agency. It claims to kill 99.9% of bacteria and viruses and kills mold and mildew. It is a 2-in-1 product that cleans and disinfects at the same time. It is an ammonia-based product. The disadvantage here is that, like bleach, it works better on nonporous surfaces.  Also, the company admits that while it will kill the mold, it does not take away the stain.

  •         Spray on the affected area.
  •         Wipe with a clean cloth.

RMR-86 Pro Instant Mold Stain and Mildew Stain Remover

Fortunately, the company created another product to take care of that stain after the mold has been eradicated. It is a bleach-based product. Not surprising, considering bleach is very effective for removing stains.

  •         Spray on the affected area.
  •         Wipe with a clean cloth

Mold Armor Mold Blocker

This is a great product for mold prevention. It is antimicrobial and waterproof. It can be used on porous surfaces and has gotten excellent user reviews.

  •         Spray on vulnerable areas.
  •         Repeat on porous surfaces every 3 months.

A word about wallpaper

You will want to treat your wallpaper a little differently than your unpapered walls. First, it goes without saying that you should test your cleaning product and method on a less visible area first.  Other tips:

  •         Rub gently in a circular motion.
  •         Don’t soak the wallpaper with water

Preventing mold in your home

When mold and I first got acquainted several years ago, I was completely taken by surprise. I started to smell something strange in the air but was unable to locate the source for several weeks. It seemed to be coming from my closet, but I wasn’t sure.

One day, I pulled out a pair of my favorite shoes and thought that they had come alive. They were covered with what looked like fuzzy, green hair! And that was how mold and I first met.

Believe me when I tell you, that there is nothing worse than having to wash everything in your closet all at once. That is how I felt at first. Then I realized there is something worse– having to throw away items that are not washable. Like that expensive Italian leather belt you love.

So my advice is to be vigilant in all places where mold can be a potential problem. This includes any place that doesn’t get a lot of light or air circulation like in a closet or a basement. It also includes any humid environment like in a bathroom or bedroom. That’s right! A bedroom. The enclosed space of a bedroom (especially with the door closed) is a mold paradise waiting to happen. It is because the hours of night-breathing increase the humidity in the room. Don’t believe me? Read this article.

Open a window

The easiest thing you can do to prevent mold growth is to open your windows and let in light and air. Mold hates sunlight and circulating air. Do this every day for a couple of hours in all the rooms of your home.

Install an exhaust fan

In areas with high humidity like in bathrooms and basements, it could be worthwhile to install an exhaust fan. These pull moisture out of the air and send the humid air outside. The investment now could save you time and money later.

Use a dehumidifier

These are wonderful machines that help reduce humidity, dust, and mold. Imagine all the time you can save on cleaning. There are two types, a compressor dehumidifier, and a desiccant dehumidifier.

The compressor version works much like a refrigerator or air conditioner. It actually draws the warm, humid air inside and replaces it with cool, dry air. These work well in warm climates and are relatively cheaper to run. Unfortunately, they are also noisy and bulky. And they don’t work well in cold weather because the machine has to be colder than the surrounding air in order to work.

Desiccant dehumidifiers work like a sponge and are quieter and more compact. They can be used in both warm and cold climates and are cheaper to run. They also last longer and due to their size, are portable. Unfortunately, they are more expensive.

There is a wide range of dehumidifiers on the market today. Some can be quite pricey. You will need to do your homework when buying one of these as they vary greatly in terms of their features. The price range is pretty wide and one of these can cost you anywhere between  $150-$400.

Moisture Absorbent boxes

I personally love these. These are little boxes with refillable packages of calcium chloride. Calcium chloride is a type of salt. But please don’t eat it! It is as, if not more, harmful than the mold we are fighting against! It is actually the same compound used for ice control on roads in the winter. Here is how it works. Calcium chloride packets sit on top of a water collection box. The moisture is pulled out of the air and transferred to this box.

 You do have to empty the water and replace the calcium chloride packets about every 1-3 months depending on how much humidity is in the area. There are many companies out there that sell these but I use DampRid. They offer different-sized boxes that range in price from $13-$26. They also make hanging packets for your closet rod that sell for about $11 each.

Mold-resistant building materials

Try painting with mold-resistant paint. You will have to reapply every now and then, but it really does prevent mold growth. I can tell you from personal experience that you need to have several weapons in your arsenal and this is a great one. If you are building or renovating your home, consider using mold-resistant wall materials. Mold-resistant drywall has fiberglass instead of paper. This prevents moisture and mold growth. And it is especially useful in rooms with high humidity like in bathrooms.

Prevent water from entering your walls in the first place

Rainwater and water from burst or leaking pipes will create moisture in your walls. This is the first step to mold formation. Why not do everything in your power to prevent this? 

  1.       Clean your gutters. Call in the professionals if you can’t do this by yourself. I do this twice a year to be on the safe side.
  2.       Repair leaking or burst pipes immediately. Don’t wait. As soon as you see signs of wet areas on ceilings and walls, investigate the source. Then take care of these problems immediately.

Insulation

I have saved the best for last. A properly insulated home will maintain dry conditions which are key to preventing mold from growing. Insulation of your exterior walls, pipes, and around your windows is your first line of defense in preventing moisture and mold.

Final Comments

I cannot stress enough the power of prevention when dealing with mold. But never fear, if the mold is here, you will be able to take care of the problem quickly and easily. Just take a deep breath (well, maybe not near the mold) and follow my advice. Good luck! 

 

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