How to Fix a Cement Patio

If you have a cement patio that has seen better days, you can repair it with a concrete overlay. Patio repairs with an overlay can hide cracks and areas damaged by normal wear and tear. You can also choose to resurface patio concrete with a variety of colors and textures if you wish. This can be a do-it-yourself project if you have experience working with concrete products. A successful repair is dependent on how well the new concrete bonds with the old. Careful preparation of the existing surface is key to successful patio repairs.

Things You'll Need

• Broom
• Hammer
• Chisel
• Power washer
• Dish detergent
• Bucket
• Garden hose
• Fabric tape
• Concrete patching compound
• Putty knife
• 1-by-2-inch furring strips.
• Stakes
• Sand
• Cement
• Concrete color
• Mixing containers
• Paintbrush
• Shovel
• 2-by-4 board
• Float
• Non-stick stamping spray
• Stamping tools

Instructions

1. Use a hammer and chisel to break off any weak portions of the existing patio cement. Clean any debris out of the cracks. Wash the surface using a power washer. If you don't have a power washer, wash the patio first with a mixture of three or four drops of dish detergent mixed into a gallon of warm water. Rinse the patio well with a garden hose. Allow the concrete to air dry.

2. Apply a layer of fabric tape into cracks on the surface. Cover the cracks and tape with concrete patching compound. Work the compound into the cracks with the edge of a putty knife. Smooth the top so it is level with the existing concrete surface. If the cracks are small, you may skip this step.

3. Build support forms around the outside perimeter of the patio with 1-by-2-inch furring strips. Only add enough height for the amount of new concrete you are pouring. Keep the forms level, but do allow for some slope so the patio can drain. Hold the forms in place with stakes driven into the ground with a hammer along the outside edge.

4. Mix enough concrete for the patio. Use the ratio of two parts sand and one part cement. If you plan to add aggregate, mix it in, but choose small stones, especially if you are pouring a very thin layer of concrete. Add color at this time if you are using it. Stir in enough water to make the concrete mixture the consistency of pancake batter.

5. Separate a small amount of concrete mixture from the rest of the batch. Add more water to this batch to make it the consistency of paint.

6. Pour the thin mixture over the patio. Work it on to the entire surface with an old paintbrush. This thin mixture helps the old surface bond with the new one.

7. Pour the thick concrete mixture over the patio before the thin mixture dries. Use a shovel to work the concrete into all corners. As the concrete sets up, pull an old 2-by-4 board back and forth across the tops of the furring strips as a screed. This helps to level the concrete. Add more mixture as necessary to level the concrete pour.

8. Use a float to smooth the surface of the concrete as it dries. When the concrete is almost set, you can stamp it or texturize it with special tools. Spray non-stick spray on the tools before you use them. If you just want a simple texturized surface, scrape a broom across the surface of the concrete.

9. Allow the concrete to cure at least 72 hours before using it.

Tips & Warnings

• Try to pour the concrete on days when the sky is overcast and the temperature ranges between 50 and 60 degrees Fahrenheit.

References

• Ask the Builder: Resurfacing Concrete
• Concrete Network: Resurface Driveways -- Step-by-Step Guide to Fix Concrete Surfaces