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mold concrete block wall

How to Get Rid of Mold on Concrete Block Walls

According to the 2021 Old Farmer’s Almanac, this winter is going to be warmer and wetter than usual. Perhaps that’s what brought you here today. Is your basement collecting more moisture this winter? Have you noticed a musty smell or discoloration on your basement walls? If so, then the most-likely culprit is mold. It’s time to figure out how to get rid of mold on concrete block walls—and fast!


Why Concrete Blocks are Susceptible to Mold

Concrete blocks are made up of water, aggregate (gravel, rock, or sand), and Portland cement. The aggregate acts as a filler while the Portland cement acts as a binding agent. Many of the ingredients in Portland cement (what is commonly used in poured concrete today) are anti-fungal, such as lime.

Portland cement is created by pulverizing and measuring out specific proportions of the following materials:

– Alumina: sourced from bauxite, clay, or recycled aluminum.
– Gypsum: sourced alongside calcium oxide from limestone (below).
– Iron: sourced from clay, fly ash, iron ore, or scrap iron.
– Lime (or calcium oxide): sourced from calcareous rock, chalk, limestone, shale, or shells.
– Silica: sourced from argillaceous rock, clay, sand, or old bottles.

Cinder blocks (often confused with their concrete cousin) tend to be antiquated but can still be found in older buildings. They contained cement and cinder ash. Today, new composites of cinder blocks are being manufactured that have a special blend of concrete ingredients and volcanic pumice or coal. Volcanic pumice and coal are both anti-fungal, as well.

Fun Fact: Roman concrete was an ideal choice for building. Not only was its hydraulic-setting composition (meaning: it could pour and cure under water) unique in all the world, many of the Roman concrete structures remain to this day because the composite contains volcanic ash, which made an inhospitable environment for mold and other microbials that would have molecularly broken down the blocks over time. Sadly, the exact secret composition of Roman concrete was lost alongside the fall of the Roman Empire itself around 476 A.D.

Whether you have concrete blocks, poured cement, or old or new cinder blocks, the ingredients are relatively the same and provide the same amount of protection against mold growth within and throughout the structure itself. The problem lies in the fact that both concrete and cinder blocks allow for the re-absorption of water. Strangely enough, this actually restrengthens the molecular structures of the blocks themselves. At the same time, however, because they are so porous and have a high proclivity toward moisture, this allows for the risk of mold growth.

Thankfully, the concrete or cinder block itself does not supply mold with a food source. Unfortunately, it is the layer of dust and other contaminates that settle on the surface over time that can provide plenty of nutrients for a mold to grow.


How to Get Rid of Mold on Concrete Block Walls

Theoretically, if you kept your concrete or cinder block walls clean of dust and debris, and were able to control the temperature and moisture level of the room, your mold problem would dry up, so to speak. Unfortunately, even if these measures are taken regularly, it is still possible for mold to simply lie dormant as it waits for the ideal conditions to arise again.
Therefore, if a mold problem has already arisen, you will have to take extra mold-fighting steps in addition to maintaining the clean, dry conditions, as well.

Before we get into the specifics of how to remove mold from concrete basement walls, you will need to have the right gear. Going in unprepared could put you at risk for mold infection and toxicity. I suggest reading up about mold containment and personal protection equipment (PPE) against mold.

After you have decided on the appropriate PPE—and are wearing it!—your first task will be to remove the moisture issue in the afflicted room. Is it a spill, a leak, or just the result of the climate? Whatever it is, clean up any puddles and repair any broken pipes. Then, well-ventilate the room by opening windows or consider investing in a dehumidifier to control the humidity immediately and long-term. (Further reading: how a dehumidifier can help get rid of mold in your basement.)

Your second task will be to clean the room and concrete or cinder block walls thoroughly, clearing away dust, debris, and/or mold itself. Whether it’s mold on the surface of concrete blocks or mold inside cinder block walls, a liquid solution comprised of a mold-killing ingredient is best and you’ll need to seal it afterward with mold-preventive vinegar.

What you will need to clean mold off concrete:
• PPE (mask, goggles, gloves, etc.)
• hard bristle brush (here are some options on Amazon; don’t use a wire brush, as it will damage the walls)
• anti-fungal laundry detergent diluted with hot-water in a spray bottle (you can use a simple dilution of borax, but I highly suggest this recipe)
• white vinegar water-diluted in a spray bottle
• anti-fungal essential oils to add to the vinegar to veil the strong scent—optional
• hot water in a spray bottle
• rags and towels you are willing to throw away
• a trash bag

Please note: All spray bottles should have a misting option—not a jet spray.

IMPORTANT: While laundry detergent is suggested, please do not use anything but a detergent that specifically highlights its anti-fungal properties. This usually entails an all-natural detergent made with essential oils. If you are unable to find such a detergent, create your own from the recipe link provided, or stick strictly with borax. Any other detergent will only provide nutrients to the mold and allow it to grow back exponentially worse.


How to Remove Mold From Concrete Basement Walls, Steps 1 – 6:


Step 1: Once you have donned your PPE and brought everything on the list into the affected room, remember to keep the room well-ventilated or leave your dehumidifier running. Then, spray the walls generously with your detergent mixture, soaking them thoroughly. (There is no need to wait for a specific period of time before you go on to the next step.)

Step 2: Start at the first area you sprayed and scrub vigorously every inch of the wall until you have finished scrubbing the entire room. The bristle brush is meant to break up and pull out from the concrete pores any visible and non-visible particles of mold-food or mold growth. (While poured concrete in the floors is less likely to have mold growth, it is wise to hit that area, too. I suggest a floor-scrubbing bristle brush instead of getting on your hands and knees with a handheld brush, though. You can find those in the Amazon link provided above, as well.)

Step 3: Spray the walls (and floor) with hot water from a spray bottle in segments one by one and then use rags or towels (you are willing to throw away) to wipe the walls and floors down. Remember to replace the towels frequently between segments so that you are not merely spreading the moldy mess. (The reason for spraying hot water is that, by the time you have finished scrubbing, the detergent and debris will have dried up and you’ll need to remoisten the walls in order to wipe them away.)

Step 4: After the walls (and floor) have been wiped clean, they will most-likely still be a little moist. That is perfectly fine. Now it is time to apply the vinegar spray. This, too, should be applied generously, which is why you might want to add an anti-fungal essential oil to it, like lavender—to help stave off that awful vinegar smell.

Step 5: Remember to safely remove and throw away the bristle brush, the rags and towels, and the PPE in the trash bag you brought with you once you are finished. It might seem like a waste of money instead of washing these things, but these items have so many nooks and crannies where mold can live, that it is best to toss them out to ensure they do not contaminate the rest of your house. This is especially important if you are dealing with toxic black mold.

Step 6: Shower and scrub your body and hair thoroughly, then opt to eat a dinner infused with plenty of garlic. You can find many anti-fungal food suggestions on MoldBlogger.

If you want to be extra thorough, add anti-fungal essential oils to your hot water bottle and repeat Step 3 twice before moving on to Step 4. This will ensure that there is absolutely no residue of detergent or mold remaining.

That’s it!


Conclusion

The answer to “How to get rid of mold on concrete block walls?” is a simple one, but if you live in a hot and humid climate, you may have to repeat this process once or twice a year. There are commercial mold sprays, but I cannot in good conscience suggest them due to their highly corrosive ingredients. Some PPE will not be able to keep your mucous membranes (mouth, nose, throat, eyes) safe from such chemicals, and it would be a shame if, in the process of saving you and your loved ones from mold, you inadvertently exposed them to chemical burns via inhalation. That is a very likely outcome if you are working on an entire room that had poor ventilation to begin with.

If you are still curious as to why ingredients such as borax and vinegar are worthy mold fighters, please feel free to read these articles that can answer the following questions:

How to clean mold off basement walls with borax? (This article is all about Borax and why it is a useful and safe mold cleaner.)

Will vinegar clean mold on concrete? (This article describes how vinegar can kill about 82% of known molds and help prevent future outbreaks.)



Article by Amanda Demsky

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Under The Hood: Investigating Car Mold

Cars. You gotta love ‘em, right? Yet along with all their magnificence comes the potential for problems – enough, quite frankly, to Exhaust you (and your bank account).

If you’re wondering what on earth a blog dedicated to mold is doing talking about cars, then you’re in luck, as it means you’ve never experienced the godforsaken relationship between the two. For everyone else, however, you know what’s coming and it’s enough to drive you round the Benz.

Yup, that’s right. Car mold. The unsightly, smelly, unhealthy fungus encroaching on your beloved, dependable, otherwise obedient vehicle that should really, when you think about it, be mutually exclusive. Seats, carpets, steering wheel – nothing is safe – especially when you consider the perfect breeding ground that a car can become when locked up for an extended period during wet weather. It’s just not something you can afFord – especially if you’re hoping to use your car as a Pickup. “WHAT SHALL WE DO? you cry.” Pipe down, dear readers, we have – as ever – got tips by the Truckload in what we will this week call our Mold Manual.
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Preventing Mold During Construction

One of many things to take into account when building a house or any other facility is the growth of mold during the construction. Mold is everywhere, so it stands as huge and possible threat that can slow the construction and increase costs of replacing affected materials as well as costs of remediation. Depending on climate and location, some construction sites are more susceptible to moisture that later result in moldy buildings. The least expensive way to deal with the mold is the prevention and certain measures undertaken before and during the construction can go a long way.
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What do you do when you’ve spotted mold in your home? You’ve heard of all the negative effects mold can have on your health and it can really ruin the appearance of a room, so of course you want to get it cleaned up quickly. For larger mold infestations, you’ll have to call in the professionals, but if you’re looking to clean up surface mold you can handle it up yourself with just a few steps.
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Dangerous Signs of Mold Allergies in Children and What You Need to Do About It

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Mold can take its toll on your heating and cooling system. The only time that mold is a serious issue, however, is when there are clear visible signs of mold or strong odor while your HVAC system is operating. Areas to check for signs of mold include air ducts, cooling coils, drip pans, and intake vents. When there’s an obvious odor of mold without any visible signs of mold, a professional needs to inspect your system to determine the source of the mold.
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Household mold is one of the most dangerous toxigenic matters that can be found inside the home. Exposure to mold has been shown to cause health problems in people who reside in a house that has a mold issue. There is a reported link between mold exposure and upper respiratory tract problems. These health conditions include but are not limited to upper respiratory tract conditions such as coughing and asthma related symptoms. People with sensitivity towards molds may experience severe reactions such as fever and shortness of breath that can be a precursor to even more problems as more time is spent around the mold. Young children and the elderly are also highly susceptible to illness due to exposure to mold in and around the home. Understanding what causes mold inside a house and how to prevent it is the first step to conquering the problem.
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The CDC reports that mold spores may easily enter your home via openings to the outside, such as doors, windows and even the cooling and heating system intake vents. They can attach to your clothes and remain dormant until favorable conditions are met, leading to their revival and growth. All mold needs is warmth and moisture to bloom into life, thus your bathroom makes the best place for it to thrive. It is very important to remove mold from your environment, as it can easily find its way into your respiratory tract and into your lungs, causing issues with those of us suffering allergies or asthma. The following tips will cover what you can do to keep them away from the walls of your home:
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How to Get Rid of Mold

Understanding how to get rid of mold is something that all homeowners should know. Even if you don’t see mold in your home right now, that doesn’t mean you won’t have to battle with it later. You may also have mold growing in areas where you don’t commonly look – like under the sinks, for example, where it can be very damp and small leaks can go unnoticed. Most homeowners don’t think about checking there.

How to get rid of mold, though, depends on the extent of the problem that you have with it. Some mold issues are very easy to handle, and others, like a black mold infestation, require a professional mold remediator (we have some tips on choosing the right one) to deal with them because of their size and/or severity.

“So, How Do I Get Rid of Mold?”

Knowing how to get rid of mold on your own is a great way to keep costs down and protect your family and pets from the sicknesses that can come from mold exposure. Of course, some removal jobs are too big to tackle on your own. Knowing when to get a professional is important.

For small infestations, cleaning them thoroughly is usually all you need to do. Use a cleaner that’s specifically for mold and mildew, use a bleach solution, or simply use soap and warm water. If you’re cleaning sheetrock or drywall, don’t soak it heavily. That can keep it from drying properly and cause more growth later. Cleaning the moldy area won’t solve the entire problem, though, because you have to stop the spores from coming back.

Fixing Mold Problems Yourself

To do that, you need to find the source of the problem. It could be a leaking pipe, it could be from flood damage or another type of water damage, or it could be just a buildup of moisture in a kitchen or bathroom where there’s a problem with proper ventilation. Finding the problem and fixing it has to be done – and you might need to get a professional to fix it for you.

Simple things like tightening a loose pipe fitting are easy for a homeowner to handle, but if you have more serious issues or you need an exhaust vent put in so you can get the moisture out of your bathroom or kitchen, it’s best to call in a professional. That way, you’ll know the job is done right.

Calling a Mold Remediator

Sometimes mold removal is too big of a job for a homeowner to handle. If that’s the case for you, you can call a mold remediator. They know how to get rid of mold, and they can help you by making sure mold is removed from your house and the problem that caused it is taken care of. It’s a great way to get larger infestations removed and keep them from coming back in the future.

Black Mold Removal – Where To Begin

Screen shot 2010-03-21 at 6.22.59 PMBlack mold removal can be a real trial, and it’s best left to professionals if it’s a large area. There’s no reason to risk harm to your health and potential damage to your home when you can get professionals to handle the issue for you. For small areas, though, you may be able to remove black mold yourself.

Understand The Process

Whether you try to do it yourself or hire a company it’s a good idea to know how the black mold removal process is handled. That way, you’ll be prepared for any issues that might come up and you’ll be knowledgeable enough to make sure the job’s being done right – no matter who’s doing the work.

Identify The Source

The first thing you should do with black mold removal is identify the source of the moisture problem. If you don’t know where the moisture (and, therefore, the mold) is coming from, you won’t get it stopped and the mold will continue coming back. Flooding, water leaks – including slow ones, and even high humidity can all contribute to the growth and recurrence of black mold.

Stop The Leak

Stopping the moisture or the leak from causing further damage is the first step with black mold removal. From that point, the cleanup needs to begin. Black mold isn’t something you can just spray with an antibacterial spray like Lysol and forget about.

Contain The Spores

If the area is a small one and you’re going to handle the cleaning of it yourself, you should first seal off the room so that mold spores don’t drift around. They can easily get into the air, mix in with dust and dirt, and get carried throughout the house. By isolating them to one room and not letting them get into the rest of the house, you’ll be better off and healthier. The cleanup will be easier, as well.

Avoid Further Contamination

Even for a small area, it’s important to seal off the room so you don’t risk any further contamination in the rest of the house. Once you’ve sealed the room, make sure the moldy area is damp. If it’s dry, mist it lightly. Dry mold spores are very quickly airborne. Keeping them damp is another way to help cut down on contamination.

Use Air Power

If the room you’re working in has a window, it’s a good idea to open it and place an exhaust fan in it, because any mold spores that do get airborne will be drawn that way and removed from the house. If you don’t have a window in the room, don’t just run a fan – you’ll just blow the black mold spores around and risk inhaling more of them.

Don’t Miss A Spot!

When you clean the area – which should be done with soap and a sponge – make sure you clean the moldy area first, and then expand your work to clean the entire room. Mold spores are tiny, and you want to make sure you get all of them so they don’t try to cause you health problems in the future. If you’re unsure about your ability manage the black mold removal from your home, do the safe thing and hire a professional to handle the job for you.

Mold Removal Services – How to Choose a Mold Remediator

Finding that you have mold in your house can be very stressful, for a couple of reasons. The danger to your health can be significant, and the cost to have it removed can also be a serious issue. If you only have a small mold problem in one area of your home you may be able to take care of it yourself. However, if the problem is large, in more than one area, or has worked its way into the walls, it might not be something you can handle as a homeowner. At that point, you’d be better off calling in a mold remediator.

What Is A Mold Remediator?

Mold remediators are people who are specially trained to handle mold problems in homes and businesses. They know what they’re doing and they have the right tools, equipment and chemicals to get the job done. They guarantee their work, too, so you won’t have to worry about the mold coming back, as long as the problem that caused it (such as a leaking pipe) has been taken care of. Not all remediators are the same, so you’ll want to check them out and get the right one. Here are some things to look for:

  • Is the remediator licensed and insured?
  • What kind of guarantee is offered, and for how long? Is it in writing?
  • Are there any Better Business Bureau complaints against the company?
  • What kind of cost will you be looking at for the remediation?
  • How long will it take?
  • Will you have to stay elsewhere while the job is being done?
  • Does the remediator handle any other work, such as fixing a pipe, re-sheetrocking an area, or painting? If not, can he or she recommend someone?

It’s important to ask these kinds of questions. You don’t want to get caught unaware because you thought you had everything planned out but really didn’t. Those extra and unwanted expenses can really push your budget if you don’t get a good remediator that’s going to take care of everything for you for a fair price.

Get More Than One Estimate

You should always get more than one estimate from multiple remediators. The prices charged for services are usually similar, but there can be sharp variations.  Ask around for recommendations and carefully compare the services offered with the final price. Don’t sign a contract until your questions have been answered to your satisfaction, you’ve checked with more than one company, and you feel comfortable with the remediator you’ve chosen to do the work.

Make Sure You’re Comfortable With The Remediator

Tools and equipment and know-how are important, but personality matters, as well. The remediator and the people he or she works with will be in your home or business, possibly for several days – depending on the extent of the problem. You want people you can trust and feel comfortable with, and you can find them by taking the time to locate the right mold remediator to handle your job.

Recognizing And Removing Mold Is The First Step With Your New Bathroom Design

We would all agree that mold is a nuisance, especially in the bathroom, but what many don’t know is that it can also be a major health hazard. Some types of mold can aggravate allergies, cause respiratory distress or even be life threatening. Because of this, it’s important to assess any mold infestation before you begin a bathroom remodeling project. Never leave any type of mold untreated during a bathroom design renovation.

What is mold?

Mold is a fungus. It grows from tiny spores that float in the air. When these spores land in a moist, temperate environment they grow and multiply. The range of what they find temperate is large, from between 40 and 100 degrees Fahrenheit. That includes most damp areas in any home.

Signs of Mold

The most recognizable type of mold fungus is mildew. Mildew is generally a surface problem and easy to eliminate using any product containing bleach.

Many times mold problems are undetectable until surface staining or a strong, musty odor appears. Once you suspect a problem below the surface it’s important to expose the infested area. If it’s a wall, cut away mushy drywall past the point of damage. If you don’t get rid of all the mold, it will just grow back.

Often mold can cause rot to set in. If mold is found in wooden studs or joists these must be treated or replaced.

The most notorious type of mold fungus is black mold. This fungus is highly toxic and must be treated with the utmost care. When dealing with black mold it’s recommended that you get a professional to clean and treat the area.

Mold can be very difficult to categorize without testing, so if you find a high concentration of mold it’s always advisable to have it tested. You can contact a professional in your community or get advice from your local health department.

Cleaning Up The Mess

There are certain safety precautions that should be followed when cleaning out a concentrated area of an infestation. Since spores travel through the air, it’s important to protect the rest of your home when treating an area. These simple precautions can keep you and your family safe.

  • Wear old clothing that can be cleaned or disposed of after the project is completed.
  • Wear gloves, goggles and a respiratory to avoid inhaling the spores.
  • Keep the room isolated from the rest of your home.
  • Turn off the heater or air conditioner, and block the air ducts in the infected room.
  • Make sure the area is well ventilated to the outside.

The bathroom is more susceptible to mold because of the near constant dampness, so when you decide to makeover your bathroom be sure to do the appropriate inspections to insure that no mold is present. And if there is even the slightest trace found, be sure to take the appropriate measures to get rid of it or you could be facing many issues and even health problems in the future.

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