Repairing concrete driveway cracks is important to prevent moisture from entering the cracks and causing further damage. Fixing cracks in your driveway is also important to improve the aesthetic appeal of the surface and give your home more curb appeal. Here's how you can repair cracks on your own.
Step 1 - Examine the Area
Before starting the repair, check out the area around your driveway looking for the cause of the crack. Growing tree roots, impacts and heavy objects sitting on the driveway may be the cause. Standing water is the most common cause of driveway cracks because it gradually seeps into the concrete, expanding and contracting with temperature fluctuations. Attempting to ascertain the cause will help prevent future damage from occurring. The size of the crack will determine the method of repair.
Step 2 - Preparing
First, clean the crack so that the surface of the driveway can bond with the repair materials. Break off any loose concrete you find using a screwdriver or chisel without making the crack larger. After cleaning the crack, remove the remaining debris using a wired brush.
Remove loose debris from the crack using an air compressor, shop vac, or canned air for cleaning computer keyboards. Essentially, you want to clean out as much dust and debris in the crack as possible.
Step 3 - Repair
For small cracks, use a textured caulk, concrete sealer, or pourable grout specifically for repairing concrete. These products work well for repairing hairline cracks in a driveway. With concrete sealer or grout, wet the crack lightly with a spray bottle of water before applying. Apply the caulk to a dry surface.
Fill the crack and use a pointing trowel to push the product into the crack. When applying caulk, overfill the crack to make up for shrinkage after drying. You can also use rubber gloves to push the caulk into the crack.
For cracks measuring more than 1/2 inch, you may have to undercut the crack to make it wider below the surface than on top. This will help the patching material stay in the crack during concrete expansion and contraction.
When using pourable concrete grout, apply 1/4 inch of grout each time. Fill the rest of the crack with sand or make several grout applications of 1/4 inch each time, allowing the grout to dry fully after each application. Before applying the grout, wet the crack lightly to make up for some of the shrinkages that will occur as the grout dries.
When using vinyl concrete patch material, follow the product's directions and only mix the amount you intend to use right away. Wet the crack with a hose or spray bottle, using a pointing trowel to spread the product into the crack.
When you're done, use the trowel to blend the final application and form a strong seal.