Spraying a vinegar solution (1 cup of vinegar per gallon of water) onto the surface, saturating it fully, should kill most strains of mold. Vinegar spray can be followed by power washing or manual hand scrubbing to remove the dead mold.
Vinegar is an all-natural solution for cleaning concrete. It kills mildew and mold, removes grime, and helps treat set-in stains. Before cleaning concrete with vinegar, it's essential to dilute it so you don't affect your sealer. Here's what type of concrete to clean with vinegar and which types to avoid.
Our top choice for mold and mildew, RMR-86 Instant Mold and Mildew Stain Remover, comes in an easy-to-use spray formula and kills all of these culprits on contact. Other types of stains are caused by manmade products, such as motor oil, paints, cleaners, and solvents.
HOW TO CLEAN MOLD FROM CONCRETE. The best solution is to scrub and clean the affected areas with a mold-killing detergent, like RMR-86 Instant Mold & Mildew Stain Remover, or a simple solution of household bleach and water. Be sure to scrub aggressively to get down into the pores of the concrete.
While it is possible to use bleach to kill mold as well, experts agree that vinegar is a much better option. Unlike bleach, vinegar can effectively kill the mold at the root, which means it's less likely to return. Vinegar is also less toxic than bleach, making it a better choice for household use.
Spray vinegar onto the moldy surface and leave it for an hour. Then wipe the area clean with water and allow the surface to dry. Any smell should clear within a few hours. While it's safe to use on most surfaces, vinegar is unlikely to be effective at cleaning mold off of soft surfaces.
For a diluted bleach solution, mix three parts water with one part bleach in a bucket. You can also use white vinegar to kill mold. Don't forget to test a small, discreet area first. Bleach and other chemicals can discolor concrete that's been colored or stained.
As a gentler cleaner, bleach can't harm concrete's durable material. Aside from being an effective cleaner and stain remover, it also acts as a disinfectant to the concrete surface.
Humidity based mold growth
Concrete is a poor insulator. During the winter months when the temperature drops, the cool surface of a concrete wall can cause condensation. In time this elevated surface moisture creates an environment conducive to mold growth.
Alkaline cleaners are great for lifting oil stains, grease stains, and other petroleum-based stains from concrete. It's an added benefit that you can use it with a pressure washer, making the job that much easier. For an eco-friendly cleaner, we recommend Oil Eater cleaner degreaser (US$15.74, Amazon).
Mold generally looks slimy or fuzzy, tends to have a raised texture, and can come in a rainbow of colors, including deep green and black. Mildew is powdery, looks white or gray, always appears flat, and grows on surfaces.
Vinegar or baking soda: These natural cleaners work well to clean cement patios with stubborn charcoal or rust spots. Mix equal parts vinegar and water, scrub the patio with the mixture, then give it a good rinse. If stains don't dissolve, try undiluted vinegar.
Molds are fungi and they can, and will, grow back after bleaching. There are 4 simple ingredients you can safely use to clean away mold in your home: white vinegar, baking soda, hydrogen peroxide, and detergent or soap.
In fact, vinegar removes mold from concrete better than bleach. Bleach will only remove the top layer of mold, causing the mold to return.
Pour enough undiluted white vinegar into the empty spray bottle to cover the area of mold growth. Spray the mold directly, fully saturating it with the vinegar, and allow the vinegar to sit for at least an hour. Don't be tempted to scrub or rinse; the mold needs time to completely absorb the vinegar.
Cleaning concrete with muriatic acid can be a highly effective solution if used correctly, providing ultra-bright white concrete and removal of many types of stains. In one application, you can remove rust stains, oil stains, algae, and paint splatter with a quick chemical application followed by pressure washing.
Use Bleach
Of course, you should dilute it with equal parts of water or a 1:1 ratio. With the mixture ready, spray it on the driveway, allowing it to sit for 10 minutes. Then, use a stiff brush before rinsing with clean water.
Cleaning concrete with vinegar or baking soda is a good option if you are looking for a natural cleaner. While cleaning concrete with bleach or detergent can be effective, it can also be toxic to plants.
Efflorescence. Efflorescence is a white powdery substance that can be seen in both sealed and unsealed concrete surfaces. It's commonly caused by water vapor migrating through the floor, bringing minerals to the surface. This is an indication of moisture intrusion, which may compromise the structural material.
To clean mold, use regular white distilled vinegar, typically sold with 5% acidity. You can also use “cleaning vinegar” with 6% acidity. Both are effective at killing mold. Generic brands are as effective as name brands.
Covering mold with paint is a waste of resources because the mold will continue to thrive and grow underneath. Eventually, the paint will bubble and peel off, and the mold will be exposed once again. Mold and mildew are an indication of potential moisture issues that need to be remediated before painting the surface.
It's often used as a natural and nontoxic alternative to cleaning chemicals when it comes to killing household mold. Cleaning vinegar, which contains 6% acetic acid, is the best type for killing mold.
So you can see why allowing the vinegar to sit for sometime is beneficial, but for too long and you're only wasting time because the vinegar will dry out eventually and become less effective. Also, you risk causing damage to the area beneath the mold when you leave the vinegar to sit on it for too long.
If you're not wearing any Personal Protective Equipment (PPE), you're inviting all of those mold spores to settle on your clothing, the area you're cleaning, your shoes (allowing mold to travel to other areas in your home), in your eyes, and up your nose into your upper respiratory system.