Repair concrete that is solid and has one problem. Replace concrete that has lost its support or has broken into many pieces. The situations below are the ones people ask us about most often. The dollar amounts in the headings are the customers' own numbers.
My 20-year-old driveway has one section sunk by the garage and I was quoted $9,000 to replace it all. Do I need to?
Probably not all of it. One low section at the garage usually points to loose fill beside the foundation or water from a downspout, and the other panels may be fine. Have that section lifted, or cut out and repoured on a compacted base. Ask the contractor who quoted $9,000 what is wrong with the other panels. If they are level with tight cracks, a single-section repair costs a small share of that.
Repair for $7,000 or replace for $14,000 if I am selling in two or three years?
Go by what the $7,000 buys. If it fixes a specific cause on a mostly sound slab, the repair should last past your sale and you keep $7,000. If it is patching on a slab that moves every winter, it may look bad again by the time you list, and you would have spent $7,000 and still face the $14,000 question. Ask both contractors what will look different in three years.
I have a few long cracks and I am selling the house. Repair, replace or leave it?
Level, narrow cracks can be cleaned and sealed, and that is normally enough. Buyers and inspectors pay attention to uneven edges, trip hazards and water running toward the house. Fix those. A full replacement before a sale rarely pays for itself unless the driveway is in pieces. Talk to your agent about what must be disclosed.
One contractor says remove it, another says pour a new layer over it. Who is right?
The slab decides. Knock on it, look for sunken or rocking panels and check the cracks. A new layer bonded to a sound, stable slab is a fair repair. A new layer on a slab that moves with the clay will show every old crack again. Ask the overlay contractor how thick it is, how it bonds and what happens at the garage door and the sidewalk where heights are fixed.
My 30-year-old driveway has root cracks and my budget is tight. Can I just grind and patch?
Yes, as a holding measure. Grinding the raised edges removes the trip points and flexible sealant keeps water out of the cracks. That can buy a few years on a tight budget. The roots will keep growing, so expect to do it again. When you do replace, the root question has to be answered first, sometimes with an arborist.
I have many small cracks and no sinking. Is sealing or resurfacing enough?
Often, yes. Fine cracks on a flat slab are mostly a surface matter. Sealing the cracks keeps water out of the clay, and that slows further movement. Resurfacing gives a new face if the look bothers you. Neither is enough if the cracks are widening or the surface sounds hollow when tapped.
What signs mean a slab cannot be saved?
- One side of a crack is higher than the other and the gap keeps growing.
- Panels rock or sound hollow under a car.
- The slab is broken into pieces smaller than a few feet across.
- The surface crumbles deep, not only on top.
- Water runs to the house and the slope cannot be corrected by lifting.
The real number for your job comes from a free visit, where we measure and look at the ground. Call (925) 690-1468 or text a photo of the area.