Because of cars, the lawn mower, tools, motorcycles and other outdoor equipment, dirt build-up and oil and grease stains are inevitable on a concrete garage floor.

Unfortunately, you are not always able to address a mess right away, or maybe you're looking to clean oil off your concrete garage floor that's been there for who knows how long. Unless sealed, cured concrete is not a hard, dense rock - the mixture of cement, sand, and aggregate is porous after it is mixed with water and cured. This allows stains like rust and oil to penetrate down into the surface.

To remove these stains and get your concrete clean, you need something that will also sink in and lift the offending spot. Cat litter, sawdust, baking soda, and other absorbent materials remove fresh spills, but don’t do much about what sinks into the surface.

Muriatic acid is sometimes used to clean concrete garage floors. But the binder in concrete, called Portland cement, dissolves when it comes into contact with an acid. Plus, acid-based cleaners pull calcium hydroxide out of the hardened concrete, which then quickly forms a white, dusty material called efflorescence. This material can become so heavy and visible that you'll need to clean it off of your floor.

Another cleaning agent that is widely believed to be the best way to clean a garage floor is trisodium phosphate (TSP). It is strongly alkaline, so it will not harm the concrete floor, but this also means it could cause skin irritation and even burns. TSP is also very bad for the environment. If it ends up in lakes and streams, the phosphates trigger an overgrowth of algae that results in a depletion of oxygen levels in the water, which can endanger fish and aquatic plant life.

Simple Green Oxy Solve Concrete and Driveway Cleaner can be used with a pressure washer or for manual cleaning of concrete surfaces including driveways, sidewalks, patios, and walkways. The non-corrosive and non-degrading formula utilizes the natural power of peroxide to provide high-performance cleaning. It removes oil stains, grease, grime, and most discolorations. Its biodegradable* formula is safe for lawns and pets.

Thoroughly clean your garage floor once or twice a year using the instructions below.

Directions for Cleaning Garage Floors:

1. Clear the floor. Move any cars, bikes, tools, boxes, and other items out of the garage.
2. Sweep. Clean your garage floor first by sweeping to remove dirt, leaves, grass clippings, dead bugs, efflorescence, etc.
3. Apply Simple Green Oxy Solve Concrete and Driveway Cleaner. Mix 2 cups of Simple Green with 1 gallon of warm water in a separate container.
4. Scrub. Dip a stiff bristle brush or push broom into your solution or lightly pour it onto the concrete. Scrub the floor in sections. It's best to start far away from the door and move toward it as you clean so you won't have to step all over your freshly cleaned floor.
5. Soak. Let the cleaning solution soak for 5-7 minutes to penetrate stubborn stains. Do not allow it to dry on the surface.
6. Rinse. If you haven't already, open the garage door. Turn your garden hose on very low, and again, start farthest away from the door. Rinse the entire floor with clean water and allow it to runoff toward the street. Simple Green Oxy Solve Concrete and Driveway Cleaner meets the U.S. EPA's Direct Release criteria, meaning it is safer for outdoor use and contact with soil, oceans, lakes, and streams.
7. Repeat. Move to a new section and repeat until the entire floor is clean.

TIP: Once you've cleaned your garage floor, you can prevent future stains by coating the surface with a concrete sealant, epoxy or paint.