Concrete parking lots are very durable. They bear consistent heavy weight as well as extreme weather changes. It is a wonder the concrete can go many years without repair. Eventually the moisture and wear and tear cause cracks and flaking of the surface (spalling). This leads to areas that break apart and need patching. Foundation failure would require a more intensive fix, but normal concrete parking lot repair is a do-it-yourself project.
Things You'll Need
- Garden hose
- Cement overlay or Portland cement or gravel
- 2-by-4 beam
- Bonding glue
- Circular saw
- Smoothing tool
Repairing Concrete Spalling
Use a push broom to remove dirt and flaked off concrete materials. Spray down the area needing repair with a garden hose. Allow the area to dry for about an hour.
Mix a batch of polymer-modified cement overlay in a small wheelbarrow. This product is available at all home improvement centers. Follow the mixing directions on the package. Scoop the cement overlay out of the wheelbarrow using a shovel and spread evenly over the spots needing resurfacing.
Run a long handled smoothing tool or a small length of 2-by-4 wood over the surface to level it out. Allow the overlay a week to settle before allowing vehicles access to the site.
Spray on a waterproof sealant to avoid spalling (flaking) in the future.
Clean the area of the concrete parking lot needing patching using a stiff broom and a garden hose. Allow plenty of time to dry before repairing.
Mix enough concrete for the patch job. Add 50 percent Portland cement and 50 percent gravel in a wheelbarrow. Add water and mix with a shovel until the consistency is plastic enough to work with. Concrete that is too watery or stiff is not useable.
Apply a cement patch bonding glue to the area that needs fixing using a paintbrush. This product will help the patching material bond with the old concrete. Fill in the hole with the concrete mixture and smooth with a small length of a 2-by-4. Allow three or four days for the patched areas to settle.
Spray the entire parking lot surface with a concrete sealant to help lock out moisture.
Repairing Concrete Cracks
Router the crack with a circular saw and concrete cutting blade. Make the crack wide and deep enough to be receptive to joint repair sealant. The crack should be at least one-quarter of an inch deep.
Fill the crack with cement joint sealant and follow the label drying instructions. Smooth over the cracks using a small putty knife.
Prevent future moisture damage by spraying the parking lot with a concrete sealant. Home improvement centers carry high-quality sealant products.
Tips & Warnings
- Askthebuilder.com offers useful advice on choosing the right patching additives for the concrete patch material. The additives help in bonding the old and new concrete together.
- Wear safety glasses and gloves when working with concrete or cement. The chemicals can burn exposed skin.
- Photo Credit priyeshpomal; Photobucket.com