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How to Get Rid of Grease Stains on a Garage Floor

Don't let those grease and oil stains on your cement or concrete floor just sit there.

by John D. WagnerUpdated 10/06/2024
A man pouring a cleaning fluid and scrubbing a grease stain

Grease stains can be unsightly and stubborn, marring the appearance of your garage floor. These stains on often come from engine oil, transmission fluid, or lubricating greases used in vehicle maintenance. Automotive greases are typically more stubborn than food-based ones due to their synthetic composition and additives.

Our guide will walk you through the process of removing grease stains from a cement or concrete floor, from do-it-yourself (DIY) solutions to professional treatments.

Immediate Actions To Take After a Grease Spill

Taking the right steps immediately after a fresh grease spill can prevent the stain from setting and make the cleaning process much easier. Here are the first things you should do when you notice a grease spill.

Sop Wet Areas

As soon as a spill occurs, grab paper towels or a clean cloth to blot up as much of the excess grease as possible. Avoid rubbing the area, as this can spread the grease and push it deeper into the surface. Instead, gently press down to absorb the liquid.

Apply Absorbent Materials

After blotting, sprinkle a generous amount of cornmeal or sawdust over the stain and let it sit for at least three hours. This will help draw out any remaining grease from the surface. After the waiting period, sweep up the absorbent material along with the absorbed grease.

DIY Methods for Removing Grease Stains

These techniques use common household items and are particularly useful for concrete surfaces like garage floors or driveways.

Use the Dishwasher Detergent Technique on Fresh Stains

  1. Sprinkle dry dishwasher detergent directly onto the wet stain.
  2. Allow it to sit for a few minutes to absorb the grease.
  3. Pour boiling water over the area.
  4. Scrub vigorously with a stiff brush.
  5. Rinse thoroughly with clean water.

The hot water activates the detergent, helping it to emulsify and lift the grease from the concrete.

Using Concentrated Laundry Detergent on Older Stains

For slightly older stains, concentrated laundry detergent can be a powerful ally. Follow these steps:

  1. Apply a generous amount of concentrated laundry detergent to the stain.
  2. Use a stiff brush to work the detergent into the stain, creating a lather.
  3. Scrub thoroughly, applying pressure to penetrate the surface.
  4. Rinse well with a hose, ensuring all detergent is removed.
  5. Allow the area to dry completely.
  6. Repeat the process if necessary for stubborn stains.

This method is particularly effective for deep cleaning various surfaces, including concrete and some fabrics.

Tackling Set-In Grease Stains

Set-in grease stains require more aggressive treatment. These methods are designed to break down and lift grease that has had time to penetrate the surface.

The Trisodium Phosphate (TSP) Method

TSP is a powerful cleaner that can tackle tough, set-in grease stains. Here’s how to use it safely:

  1. Ensure the area is well-ventilated.
  2. Put on protective gear, including gloves and goggles.
  3. Sprinkle TSP directly onto the stain.
  4. Allow it to sit for 15-30 minutes.
  5. Scrub the area with a stiff brush and hot water.
  6. Rinse thoroughly with clean water.
  7. Repeat if necessary.

Remember, TSP is a strong chemical, so use it with caution and follow all safety guidelines on the product label.

Enzymatic Cleaners for Stubborn Stains

Enzymatic cleaners use biological compounds to break down grease molecules. They’re particularly effective on organic stains.

  1. Choose an enzymatic cleaner designed for grease removal.
  2. Apply the cleaner according to the manufacturer’s instructions.
  3. Allow it to sit for the recommended time, usually several hours.
  4. Scrub the area gently to help the enzymes penetrate.
  5. Rinse thoroughly and allow to dry.
  6. Reapply if needed for particularly stubborn stains.

Steam Cleaning Techniques

For porous surfaces like concrete, steam cleaning can be an effective way to lift deep-set grease stains. Read our guide for more details on steam cleaning.

  1. Rent or purchase a steam cleaner suitable for your surface.
  2. Pre-treat the stain with a degreasing agent.
  3. Follow the steam cleaner’s instructions to apply hot steam to the stain.
  4. Use the machine’s brush attachment to scrub as you steam.
  5. Repeat the process, focusing on heavily stained areas.
  6. Allow the surface to dry completely.

Professional Solutions for Severe Grease Stains

When DIY methods fall short, it may be time to consider professional solutions. These approaches are typically more powerful and can handle even the most stubborn grease stains.

Chemical Treatments

Professional-grade chemical treatments can break down grease at a molecular level. These are often applied by experts who understand the proper application and safety precautions:

  1. A technician will assess the stain and surface type.
  2. They’ll choose an appropriate chemical treatment.
  3. The area will be pre-treated and the chemical applied.
  4. After allowing time for the chemical to work, it will be thoroughly rinsed.
  5. This process may be repeated for severe stains.

Pressure Washing

High-pressure washing can be extremely effective for outdoor surfaces, we tested several pressure washers to find the best ones for your cleaning needs.

  1. A professional will use a commercial-grade pressure washer.
  2. They may apply a degreasing agent before washing.
  3. The high-pressure water stream will blast away the grease.
  4. Multiple passes may be needed for best results.

Concrete Resurfacing

For extremely severe stains that have deeply penetrated concrete, resurfacing might be the best option:

  1. The top layer of stained concrete is ground down.
  2. A new layer of concrete or epoxy is applied.
  3. This provides a fresh, stain-free surface.

While more invasive, this method can completely eliminate even the most set-in stains.

Preventing Grease Stains

Prevention is always easier than removal. Implementing some simple strategies can help keep your surfaces clean and stain-free.

Protective Sealants for Concrete

There are quality sealants available for most surfaces, including concrete and cement. Choose a sealant that matches your garage surface to create a barrier against grease penetration. This can be particularly effective in areas prone to automotive grease stains.

Proper Storage of Greasy Materials

Organizing and storing greasy materials correctly can prevent accidental spills.

  • Use sealed containers for storing oils and greases.
  • Place drip trays under vehicles or machinery prone to leaks.
  • Store cooking oils away from high-traffic areas in the kitchen.
  • Use spill-proof containers when transporting greasy materials.

Regular Maintenance Practices

Implementing a regular cleaning routine can prevent small grease spots from becoming major stains:

  • Wipe up spills immediately as they occur.
  • Regularly clean areas prone to grease accumulation.
  • Inspect and clean under appliances and vehicles periodically.
  • Apply fresh coats of paint or sealant to surfaces as needed to maintain their protective qualities.

Our Conclusion

By understanding the nature of different grease stains and following the methods outlined in this guide, you can effectively tackle even the toughest grease stains on various surfaces. Regular maintenance and preventive measures will go a long way in keeping your spaces clean and grease-free.

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