The Best Way to Clean Indoor and Exterior Concrete Floors

While the building material concrete was once relegated to patio, sidewalk, driveway, basement, and garage surfaces, it has moved indoors to become sophisticated floors and countertops. Concrete is exceptionally durable and easy-care if you treat it properly.

Before You Begin

To protect your floors from damage and clean them most effectively, it is essential to know what type of finish is on the concrete. Stains and spills should be cleaned up and treated as soon as possible on all types of concrete.

Sealed

• Sealed concrete is coated with acrylic resins, penetrating silicates, epoxies, or urethanes making it nonporous and stain-resistant.

Polished

• Concrete can be polished wet or dry to a glossy finish that never needs to be waxed or recoated. The level of sheen can be chosen, and the concrete can be stained to look like marble, granite, or any polished stone

Stained

• If grey isn't your favorite color, there are stains in a wide range of colors to color newly poured or older concrete. The stains penetrate the concrete and are permanent. The finish can then be sealed or left unsealed.

Stamped

• Often called imprinted or textured concrete, stamped concrete can replicate stone, brick or even wood. The concrete is usually stained and can be left unsealed or sealed to make it more durable.

Painted

• While concrete accepts stains readily, it is more difficult to achieve a durable surface with oil-based or latex paint. If the surface has been polished or sealed, the paint will not adhere properly, and peeling will occur.

Unsealed

• Poured concrete without any additional treatment is unsealed. This leaves the surface naturally porous and susceptible to stains, particularly liquid stains like oil.

Cleaning Sealed Concrete Floors

Since sealed concrete floors are nonporous, they are resistant to most stains making cleaning very simple.

What You Need

Supplies

• Dishwashing liquid
• Water

Tools

• Broom, dust mop or vacuum
• Wet mop
• Bucket or deep sink

Instructions

1. Remove Surface Dust and Debris

   Sweep, vacuum or dust mop regularly to help prevent scratches from dirt and grit.

2. Mix Cleaning Solution and Wet Mop

   Weekly, mix two gallons of warm water and two teaspoons dishwashing liquid in a bucket or sink. Mop the floor with the solution.

   Warning

   Do not use harsh cleaners, which can break down and dull the sealant. Reseal as recommended by the installer.

3. Rinse and Dry

   Go back over the floor with clean water to rinse away any soapy residue. Allow the floor to air-dry.

Cleaning Polished Concrete Floors

Polished concrete is the easiest care concrete because it never needs to be resealed.

What You Need

Supplies

• Commercial polished concrete cleaner

Tools

• Dust mop or vacuum
• Wet mop

Instructions

1. Dust Mop Regularly

   Use a dust mop or vacuum to remove surface dust and debris.

2. Clean with Commercial Cleaner

   When soiled with dirt or spills, damp mop with a commercial polished concrete cleaner that is pH-neutral. Most cleaners do not require rinsing. Always read the product directions.

Cleaning Painted Concrete Floors

Painted concrete floors can have sealed or unsealed surfaces. To protect the paint and the sealant, it is important to avoid harsh or acidic cleaners that may damage the finish.

What You Need

Supplies

• Mild all-purpose cleaner
• Water

Tools

• Dust mop or vacuum
• Microfiber mop
• Bucket or sink

Instructions

1. Dust Mop or Vacuum

   Dust mop or vacuum the floors regularly to remove surface grit and soil that can scratch the painted finish.

2. Mix a Cleaning Solution and Mop

   After vacuuming, mix a cleaning solution of warm water and an all-purpose cleaner like Whole Foods Market 365 All Purpose Cleaner. Use a microfiber mop that is only slightly damp with the cleaning solution. Do not use excessive moisture because that can break down the paint and cause it to peel.

3. Rinse and Dry

   Always rinse well with a mop dampened with plain water to remove any soapy residue and allow the floor to air-dry.

Cleaning Unsealed Concrete Floors or Exterior Concrete

Even though it is easy-care, garage floors, sidewalks, and patios will look better with a good cleaning.

What You Need

Supplies

• Trisodium phosphate
• Water
• Stain removers (varies depending on the type of stain)

Tools

• Stiff-bristled broom or shop vac
• Garden hose or bucket
• Pressure washer (optional)
• Rubber gloves

Instructions

1. Remove Loose Debris and Dirt

   Start by removing anything sitting on the concrete. Sweep away debris and dirt with a stiff-bristled broom or use a shop vac.

2. Overall Cleaning

   The easiest way to clean exterior concrete is with a pressure washer filled with a solution of trisodium phosphate and water. Wearing rubber gloves, follow the mixing directions on the product.

   If you don't have one, wet the concrete with a garden hose and use a stiff-bristled brush like push broom to distribute the trisodium phosphate and scrub away. Complete the cleaning with a good rinse and allow the area to air dry.

3. Remove Grease Stains

   Sprinkle the stained area with a layer of cornstarch or dry kitty litter. Let it remain on the stain for at least three days to absorb the oil. It takes that long because unsealed concrete is porous and the oil goes very deep. Vacuum away. Repeat if needed.

4. Food and Beverage Stains

   Mix two tablespoons of dishwashing liquid with one quart of water. Using a stiff brush, apply the mixture and scrub well. If the stain is oily, apply the liquid directly onto the stain and scrub. Rinse well with plain water.

5. Tire Marks

   Wet the area first and spread a degreaser over the stains. Let the cleaner work for at least four hours and then scrub with a stiff brush. Rinse well.

6. Rust Stains

   If the rust stains are light, pour distilled white vinegar on the stains and let it work for at least 30 minutes and then scrub with a stiff brush and rinse. If the stains are large and dark, use a commercial rust remover that contains oxalic acid.

7. Mildew Stains

   Wearing rubber gloves, mix two tablespoons powdered laundry detergent, two tablespoons trisodium phosphate (TSP), and one-quart water.

   Scrub the mildewed area with a stiff-bristled brush and the cleaning solution, then rinse well.

   For extremely heavy mildew stains, use a chlorine bleach and water solution instead. Mix one cup of bleach per gallon of water and scrub the area with a stiff brush and then rinse well.

   Warnings

   • Do not mix bleach with other cleaners.
   • Wear protective clothing (bleach stains cannot be removed) and use only in a well-ventilated space.
   • Protect shrubs and grass from the mixture.