How to Smooth a Rough Garage Floor

Apply Patching Compound

• 1

  Remove all of the items from the floor of the garage. Thoroughly clean the concrete floor with a pressure washer. If you don’t have a pressure washer, wash the floor down with a garden hose then scrub it with a mixture of hot water and a few drops of dish washing detergent. Rinse the floor well and allow it to air-dry.

• 2

  Clean out any debris in the cracks in the concrete with a shop vacuum. If the concrete near the cracks appears to be crumbling, use a hammer and chisel to chip away the loose concrete.

• 3

  Prepare patching compound, according to the label directions. Some products come premixed and ready to use. Apply the patching compound to the cracks with a putty knife. Work the compound into the deepest portion of the cracks to fill each one full. Create a smooth surface on the concrete by pulling the putty knife over the top of each patch and feathering the edges of the compound onto the nearby concrete. Follow the manufacturer's recommendations for drying times.

Apply the Overlay

• 4

  Place duct tape over any expansion joints on the garage floor to protect them.

• 5

  Mist the entire surface of the garage floor with a garden hose equipped with a spray nozzle. Remove any water puddles with a long-handled squeegee.

• 6

  Mix the overlay product with water, according to the packaging directions. The overlay will create a thin concrete covering for the rough floor. For lump-free mixing, add any coloring agents or texture to the dry overlay product before adding water. You can add more color or texture once the overlay product is mixed, but this is not usually recommended.

• 7

  Pour the overlay mixture onto the concrete floor. Overlay is self-leveling, but you still need to use a long-handled squeegee to work the overlay into corners and hard-to-reach areas.

• 8

  Run a concrete edge tool along the perimeter of the overlay 20 minutes after you pour it. Let the overlay dry completely, per the manufacturer’s recommendations, before walking on it or returning items to the garage. Remove the duct tape from the expansion joints.