How to Clean a Concrete Basement Floor

Last Update:

Disclosure: This post contains affiliate links and I may earn a small commission if you purchase through these links.

Concrete is a highly versatile building material, which is why it’s popular for building. Also, it has fair resistance to stains, and it can be sealed to live for a long time.

However, a lot of people don’t know how to clean a concrete basement floor. If that’s what you’re looking for, you’re in the right place!

In the following article, I’ll walk you through every step of the process, so you can clean different types of stains and keep your basement in mint condition. Let’s dive in!

Why Basements Are Hard to Clean

Unlike most rooms in our houses, basements are exceptionally challenging when it comes to cleaning. Here’s why:

  1. They have lower ventilation, which can make you uncomfortable while cleaning.
  2. They’re hidden out of sight, so dirt and debris pile up quickly over time.
  3. They have perfect conditions for smelly mold and mildew to grow (high moisture and low light).

What Items Do You Need for This Project

Depending on what you want to do, you’ll need various items for this project. Here’s a list of all the items you’ll generally use in all aspects of basement floor cleanup:

  • Protective eyewear and mask
  • Gloves
  • Protective suit
  • Broom
  • Duster
  • Vacuum cleaner
  • Mild dish soap
  • Mop and bucket (ideally, a microfiber mop works better than the normal one)
  • Scouring brush with nylon or wire bristles

How to Prepare the Concrete Basement Floor for Cleaning

Whether your basement floor is made of sealed or unsealed concrete, there are some preparatory procedures that you need to take care of before you head into the cleaning.

These prepping up steps would make the cleaning process easier and safer for you. Moreover, they’ll protect these items from any kind of corrosion or harm from the cleaning tools you’re going to use.

Put On Any Protective Equipment You Need

In an enclosed environment with limited ventilation like concrete basements, you need to make sure that you’re well protected while using some chemicals and cleaning formulas.

Ideally, you need to protect your hands and eyes by wearing gloves and protective eyewear. These items should be reliable enough to protect you but at the same time, they shouldn’t hinder your motion or vision.

You might need a full protective suit if you’re going to scrub the floor, because, more of your body will be in contact with the floor while cleaning.

Ensure Proper Ventilation Throughout the Process

With harsh chemicals applied and limited ventilation, things might be too uncomfortable to carry on. Remember to keep any windows and access doors open while cleaning.

In addition to airing out the room, you might also need to use the exhaust fan if you have one installed to get rid of any produced fumes while cleaning.

If you don’t have one, you might use a regular fan or a dehumidifier to keep the airflow in the basement going. This will also help you in drying up the floor quickly when you’re done.

Clear the Surface Entirely

Remove all manageable items from the basement to create an easier space to work with. This includes carpets, rugs, mats, decorations, furniture, and anything that is in your way.

You might think that this is a tedious job. But speaking from experience, you’ll need to constantly move the furniture around all the time to clean under it. So, it’s the same effort, but with much more convenience!

Get Rid of Any Loose Dust and Debris

The final step in preparation, which also counts as the first step of the cleanup project, is getting rid of loose dust.

If you mop or wipe a floor that has a lot of dirt and dust, the moisture will eventually dry and the dirt will pile up again.

Make sure that you remove all the large particles of dirt and dust. You can do that by sweeping it with a broom, then go over that surface again with a little duster.

However, I recommend that you use a vacuum cleaner because it’s much more efficient and takes less time. All the while preventing dust from clouding up the basement.

How to Clean Unsealed Floor Concrete Basement

If your concrete basement is unsealed, this means that it has enough porosity to soak up liquids and will be more prone to damage by water.

This doesn’t mean that you shouldn’t use any water in the process. Instead, you may still use a considerable amount of water to get rid of hard stains. It’s best to use it in moderation though, since leaving moisture in the unsealed concrete floor will cause some structural damage with time.

Therefore, you’ll have to clean the spilled water and liquid detergents, then dry it as soon as you’re done. As for old stains, you’ll most likely need to soften them first before using water to clean them out.

1. Use Sawdust or Cat Litter to Remove Mild Stains

If you have some fresh and mild stains that you want to remove, you can use sawdust or kitty litter for it.

These items are easy to sprinkle, and they dry up the stain into an easy to remove clump. Let them sit for a few minutes then use a broom to sweep off the mixture.

After removing the largest debris with sawdust or cat litter, use a good vacuum cleaner to remove the smaller specks of dirt and debris that didn’t stick to the mixture.

2. Mop the Floor with Soapy Water

If the stain is a bit greasy, you’ll need to use liquids to break it down first. To do that, wet a mop in a bucket of clean water to moisten the stain.

Next, add a few drops of dish soap, or sprinkle some detergent over the stain, and let it process through the stain for 40 to 60 minutes.

Make sure that the detergent used is fairly mild to avoid discoloring the permeable concrete surface.

Before applying the mop on the floor, wring it fairly to remove excess moisture. That’s to avoid damaging the concrete surface. Also, don’t use bleach because it can discolor the concrete.

However, if you need a more powerful solution, you may add about 2 to 3 teaspoons of ammonia to the soapy mix.

3. Scrub the Most Stubborn Stains with Boiling Water

After letting the solution sit for about an hour, it’s time to wash it to remove the stain. Prepare enough boiling water and pour some over the stain mix.

Once you add boiling water, use a scouring brush in a continuous circular motion to clear the stain.

4. Rinse off All Detergents Used to Get Rid of the Residue

Once the stain is gone (or mostly gone), it’s time to rinse off all the materials used while cleaning so they won’t seep into the floor.

Remember to add more rinsing cold water, and wipe with a mop, until the detergents are cleared out.

5. Dry the Floor

After using enough water to rinse off the surface, you should make sure that the floor is dry.

To do that, you simply need to get a dry mop or a piece of cloth and wipe all the wet floor until the majority of the moisture is gone.

Leave the windows open for an hour to help the remaining moisture evaporate before finishing up the cleaning process.

How to Clean Sealed Concrete Floor Basement

Unlike unsealed concrete, those treated with impermeable sealants will prevent almost all kinds of liquids from passing through the layer beneath the concrete.

For that reason, it’s usually easier to clean these surfaces without worrying about the integrity of the structure of the floor. Here’s how to take care of a sealed floor concrete basement.

1. Start with Wiping the Floor with Soapy Water for Mild Stains

After you’re done brushing the surface with a broom, it’s time to wipe the floor with a wet mop to clear out the mild stains.

You can do this on a weekly basis to keep the basement clean and fresh. Since the floor is sealed, you won’t have to worry about water seeping into the concrete.

Yet, you should still wring the mop well before wiping the floor and use little water to:

  • Prevent the water from pooling up your basement.
  • Make it easier to apply further treatments for harder stains.
  • Allow the floor to dry up quicker.
  • Avoid the formation of mold, efflorescence, and mildew in the basement.

2. Brush the Floor with Trisodium Phosphate

Trisodium Phosphate (TSP) is a highly soluble alkaline compound that works very well for cleaning between concrete blocks. Not only that, but it’s also a great compound to clean off old carpet glue residue that’s sticking to the concrete floor.

To create a TSP solution, fill a bucket with 1 gallon of warm to hot water along with 3 ounces of TSP. Mix the solution well then spray it over the dirt and grime on the floor. Next, scrub the floor with a wire brush to break off the stains.

For glue residue, leave the TSP solution over for an hour before scrubbing or scraping it with a sharp edge. Once the stain is cleared off, you should rinse the spot with clean water. If you have a drain in your basement, you can use a hose to rinse it.

If you don’t have a drainage system, simply wipe it with a dry mop, and drain the water in a bucket until the drained water is clear.

3. Use Ammonia for Hard Stains

If your basement has enough ventilation, you can also use ammonia to clean concrete surfaces successfully. It’s also exceptionally good at breaking down hard stains like dried old greases and grime.

Add a gallon of warm water in a bucket along with a quarter cup ammonia. Use a brush with stiff bristles (nylon brush) to scrub the solution on the floor. You can also add some mild dish soap to the mix.

Moreover, you can mix up ammonia with TSP to save time, although I found that they work better when they’re separate.

Similar to the previous step, finish up by rinsing the concrete with clean water then wiping it with a dry mop, if you don’t have a drainage system.

4. Dry the Floor

Even for a sealed concrete basement floor, you need to make sure that the floor is completely dry before you’re done cleaning.

A wet floor will increase the humidity in the basement, causing molds and mildew to form, and give off their stinky and musty smell. Also, it weakens the sealant on the floor over time and ruins the furniture once you return it back.

How to Eliminate Mold and Mildew in Concrete Floor Basement

Basements are known for being a perfect breeding ground for mold and mildew to prosper and grow. In addition to making a stinky smell, they also release dangerous particles in the air.

If your concrete floor stays damp for a long time, it’ll get some mildew and mold going on. Here’s how to get rid of them:

Bleach is a great choice for disinfecting the concrete floor, as it kills microorganisms, mold, and bacteria that cause a stinky smell. Mix one or two ounces of bleach with a quart of warm water then spray this mix directly over the spots of infestation.

If you don’t want to use liquids in your basement, bleach powder is a great choice too. It’s known as chlorinated lime, and it’s available in most grocery and home improvement stores.

Bleach powder in general is great for effortless cleaning because it won’t require you to scrub the floor intensely. Instead, you let them do their magic while you’re away.

Simply sprinkle some of the power over the concrete floor, and allow it to sit for a day or two, while it disinfects the floor. You can then use a vacuum cleaner, or a broom, to remove all the particles from the floor along with dead mildew.

Before you attempt to use this method, make sure that you’ve completely got rid of all ammonia, TSP, or any other cleaning agents for good measure. Bleach will react vigorously with alkaline compounds like ammonia to produce chloramine gas. This gas is extremely toxic and can be deadly in an enclosed setting like basements.

After you successfully get rid of all mold and mildew in the basement, make sure that you don’t let them grow back. It’s best to keep the windows open for a specific period of time every day to let fresh air in.

Also, you can use fans to improve the air circulation in your basement, or install a dehumidifier there, to get rid of all the moisture trapped in the concrete floor.

How to Remove Efflorescence from Concrete Floor Basements

Efflorescence is a phenomenon in which salts and minerals from water are deposited onto the concrete after water seeps into concrete or evaporates. This leaves a visible white powder residue over the floor. It makes the basement look dusty, despite being cleaned up.

The best way to get rid of efflorescence in your basement concrete floor is by using a stiff scrub brush.

These brushes will help you loosen the white film of powdery dust off the concrete floor. Once the powder is scraped off, you can wet a sponge or a rag. Then, wring it well to wipe off the efflorescence.

If the white film shows up again in a short time, it’s usually a sign that your floor needs proper sealing.

How to Get Rid of Rust Stains in Concrete Floor Basements

Rust stains are unique because they’re not easily cleaned with regular cleaning solutions and compounds. But that doesn’t mean that they’re permanent and you can’t get rid of them at all.

In fact, you can still get rid of them using some simple tools. If you have a very mild rust stain, you can actually use a stiff brush with nylon bristles to get rid of it. Avoid using metal bristle brushes because they can scratch the concrete. Additionally, they can be the cause of rust stains themselves!

Another way to get rid of rust stains is by using dry cement and a small piece of flagstone that is used as a patio paver. Both of these items can be found easily in home improvement stores.

First, sprinkle some of the dry cement over the rusty spot then rub it with a flagstone. This method is pretty easy, and you’ll start seeing results almost instantly!

What to Do When You’re Done Cleaning

After cleaning the concrete basement floor, there will be some additional steps. You might want to consider them before returning back your objects and carpets to the basement.

Here are ideas about things you might want to do first:

  • Leave the floor to dry up for 24 hours to avoid mold and mildew
  • Reseal the floor with a concrete sealant, especially if the efflorescence and mold return back quicker than they should.
  • Wax the floor and give it a fresh layer of paint.

Wrap Up

With that said, you now know how to clean concrete basement floors. As you can see, the steps in this guide can be performed with relative ease. And the tools needed for the project are readily available in grocery and home improvement stores.

Remember to never underestimate the limited ventilation of the basement and to keep the windows open while cleaning. Additionally, make sure that the floor is fully dry when you’re done cleaning.

Leave a Comment