How To Remove Black Mold From Concrete

Black mold damage to concrete can occur both indoors and outdoors. How to remove this mold from concrete and prevent future occurrences is covered in our article.

Black mold on concrete is not easy to remove, it is easier to prevent its occurrence. Ignore such a phenomenon should not be ignored, because fungus not only makes the room unattractive, spoils the quality of plaster and concrete, but also harms the health of people living in it, can lead to the development of various diseases. It is important to get rid of mold as soon as possible.

What is mold

Mold is a fungus, more complex in structure than yeast. It reproduces by spores, each of which is dormant until it gets into favorable conditions. Then begins the development, the growth of the fungus.

The number of spores in each individual specimen exceeds 1000 pcs. Most of the spores are observed in the air. For the development of black or other type of mold needs a dark, damp place: in dry and hot, it will not take root. If the air circulates poorly, stagnates in the room, the conditions are considered particularly favorable for its reproduction, development and growth.

The fungus can parasitize not only on the walls or ceiling, but also on rubber children’s toys, on food products containing a lot of glucose or acid.

See also: How to Remove Black Mold From Clothes


On a concrete wall, mold fungus can appear under favorable conditions: if the room is poorly ventilated, high humidity and low temperature, accidentally brought into it spores are highly likely to begin to develop.

Often observed in rooms where the corners are poorly heated, in places with a high groundwater level, when there are violations of the functioning of the sewer system, malfunctions in the roof drainage. If mistakes were made during construction, the risk of fungal lesions also increases.

Related article: How to remove black mold from a wood

What are the dangers

It is necessary to remove black mold, because it poses a health risk to the people living in the affected room. The spores are highly toxic.

They can penetrate into the human body from the air when breathing, through the pores on the skin. Penetration through the circulatory system by cuts is also possible.

  • This can lead to the development of:
  • asthma;
  • various allergic reactions;
  • eating disorders;
  • Severe headaches (migraines);
  • bronchopneumonia;
  • Rheumatic joint pains and other pathological processes.

Mold is especially dangerous for small children, the elderly, allergic persons, immuno-compromised persons, during illness, during recovery and during pregnancy.

Mold is dangerous even when it occurs in a room where people do not live permanently. Although the impact on health in this case is much lower, the fungus can ruin concrete, making it less durable. Because of this, collapses are possible.

See also: How to Remove Black Mold From Drywall

Preventing Black Mold on Concrete

It’s easier to prevent black mold than to get rid of it.

Simple measures

It’s important to keep your drains and downspouts running smoothly. If the first problems with these systems appear, you should get them fixed as soon as possible. You should also keep an eye on the condition of the foundation and the roof. If the waterproofing system wears out, it will be necessary to replace it in time.

It is important to ventilate rooms regularly so that the air does not stagnate. If the corners are poorly heated, you should take additional measures to insulate them. Heating devices are recommended on cold facade walls.

Information provided by

Rooms should be well lit. It is better if it is sunlight. It is important to monitor the humidity. It should not rise above 75%. You can use a dehumidifier to keep it that way. You should also keep an eye on the temperature and it is best to keep it between +65 and +74°F.

Read also: How To Get Rid Of Black Mold In The Attic

Special products

Preventive treatments can also be done with special products available at your local building society store. We recommend adding fungicides to cement mortar to prevent fungi from getting a foothold on your walls.

However, you can also use preparations designed to disinfect the premises when the house has already been built. Treatment of concrete against mold and mildew can be carried out with different intervals depending on the type of room.

Since such products are toxic, you must work with them with the windows open. Children and pets should not have access to the room for the duration of the treatment.

It is also important to use personal protective equipment to prevent the chemicals from getting on the skin, mucous membranes.

Removing Black Mold From Concrete

If mold has already appeared, you will have to take measures to eliminate it. You can do it yourself or call a special service.

Preliminary stage

Before removing mold, it is important to dry the concrete. If this preliminary step is not taken, other measures will not be too effective in the fight against parasitic fungi, states blog. The affected area is then moistened liberally with water to stop the spores from spreading.

It is important to scrape the mold off the walls, using a metal brush. Plaster will also have to be removed. Experts recommend scraping the front layer of concrete as well. All removed parts of the finish must be removed from the room.

See this as well: How to Get Rid of Mold on Dishes


An effective way to get rid of black mold fungi is the use of antiseptic agents. Choosing what to treat the surface with, you should give preference to professional means from construction stores. Folk methods are often not effective enough.

The chemical is applied to the affected area. The radius of application should exceed the area of infection by at least 3 ft. When the first layer dries, it is necessary to re-treat the surface with the chemical agent. If necessary the procedure can be repeated one more time.

It is important to correctly calculate the consumption of antiseptic for concrete to immediately get hold of the right amount. The last layer is applied antibacterial impregnation.

We also wrote about Black mold in a shower.

Safety precautions

Ways to combat fungal lesions of walls, often unsafe for humans: many chemicals are toxic, can have a negative impact on health.

When working with chemical agents, it is necessary to use protective gloves, goggles, respirator. Clothing must completely cover the body (including the head). The room must be ventilated during cleaning. After treatment is complete, you must not enter the room without special clothing for 2 days.

For some products the period will be longer; you should read the instructions for use. If there was food left in the room, you will have to throw them out.


I enjoy acquiring knowledge and sharing it. I am a long-time health advisor and blogger for over 12 years. Understanding the dangers of black mold to people, I felt it necessary to share with readers the basics of fighting and preventing black mold in homes and other living spaces.

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