Cracks regularly appear in cement walkways, porches and driveways often because of shrinkage in the concrete mixture creating tension that pulls and tears on the structure. It may also be caused by not having a proper foundation underneath the cement. This can happen when the mix has been poured on top of soft, uncompacted soil. Any cement crack that is larger than 1/4 of an inch should be enlarged before repairing it to make the cement patch more durable.
Instructions
1. Examine the crack carefully; any crack that is larger than a small hairline will need to be enlarged using a cold chisel and hammer before filling. This crack should be undercut to better support the patch.
2. Make the crack wider at the bottom than it is at the top, digging down to a minimum depth of one inch. You may need to deepen the crack in order to fill it properly with the new cement mixture.
3. Brush out any loose materials left inside the crack with a wire brush, and vacuum the crack (optional) to remove any residual silt or dust. The crack should be as clean as possible before you add the repair mix.
4. Hose the crack out with a high-pressure nozzle on a garden hose to both dampen the area and remove residual dust not removed by the vacuum.
5. Brush a concrete bonding adhesive into the hole to help the new patch adhere better. Apply with a paintbrush in the area of the crack you undercut, and let it air dry until it becomes tacky.
6. Moisten the area with plain water if you decide to forego the adhesive---using a paintbrush to get inside the crack. You should not have any standing water inside of the crack before applying the patch; the area should be damp.
7. Stir up a ready-mix concrete patch with water for cracks that are not long and extensive, or mix one part Portland cement to two and one half parts of fine sand for large repairs.
8. Fill the crack with the cement mix using a pointing or margin trowel, sliding the mix into the hole and tamping it down well with the trowel. Allow the cement to settle into the crack, adding more as needed.
9. Smooth out the cement over the concrete with the trowel until it is flush with the pavement, scraping off the excess cement.
10. Allow the cement patch to dry for two hours before covering well with plastic weighted down by rocks or boards. Keep the cement patch covered for a minimum of five days, wetting down the area of repair once daily with a garden hose to help it cure.
11. Roll on a water-based concrete sealant after the patch has fully cured.
Related posts
Repair Hairline Cement CracksAlthough cement is a durable material, it is not uncommon for hairline cracks to form. These small, thin cracks are usually the result of the cement structure or surfa...
MDF can be repaired with wood glue.MDF is a building material consisting of small wood particles compressed under high pressure. MDF or "medium density fiberboard" is used in cabinets, s...
Cement board is a building material much like drywall in appearance. While drywall has a gypsum core, cement board has a cementitious core. Manufacturers make cement board by sandwiching cement be...
Stucco finishes are durable and beautiful.Portland cement stucco (also called Portland cement plaster) is a versatile finish material for both indoor and outdoor applications in wet, dry, cold and...
Wooden cutting boards are versatile kitchen tools used to protect counter tops and tables from knife blades. With proper care, wooden cutting boards will last for many years before they must be re...
