A homeowner in Edgewood called me about what she kept calling “just a resurfacing job” — a broom-finished driveway from the late 1990s with a crack running corner to corner, a section by the garage door that rocked under a truck tire, and moss working up through a joint near the street. She wanted a stamped overlay in slate gray, something that would make the slab look new for a fraction of what tearing it out would cost. I told her what I tell most people who call about resurfacing: an overlay changes what you see, not what is underneath it. If the ground under that slab is still moving, the overlay cracks in the same places within a year or two.
What an overlay is actually built to fix
A bonded overlay is a thin layer, usually 1/4 inch to 1-1/2 inch depending on the system, applied over an existing slab to renew the surface. It can hide hairline cracking, spalled or scaled concrete, discoloration, and a worn broom finish. What it cannot do is stop a crack from reopening if the slab underneath is still settling, and it cannot fix a hollow spot under the concrete. The overlay bonds to whatever is there. If what is there is unstable, the bond is the first thing to fail.
The conditions where resurfacing makes sense
Before I take an overlay job, I want to see a few things. The slab has to be structurally sound — no panels rocking underfoot, no section that flexes when you drive on it. Cracks should be stable, meaning a crack monitor or a pencil-mark test shows no movement over several weeks. There should be no sign of pumping (fine material or water squeezing up through a joint under load) and no drummy, hollow sound when you tap the surface, which usually means a void underneath. The old surface also has to be capable of being ground clean enough for a mechanical bond — flaking paint, old sealer, and laitance all have to come off, and a slab with deep, widespread scaling from years of deicing salt often does not have enough sound material left to bond to.
The signs that mean tear-out, not overlay
A slab that rocks when weight crosses it has a support problem below, not a cosmetic one on top. Active cracking — a crack visibly wider this spring than it was last fall — means the ground is still working, and resurfacing over that is a temporary cover, not a repair. Corner spalling on more than a small share of the panels, rusting rebar that has already jacked chunks of concrete loose, and any spot you can rock by hand all point the same direction. So does a driveway sitting over old fill on a Kanawha Valley hillside that has never been checked for slope stability — an overlay on top of that is cosmetic work on a geotechnical question.
Thickness, wear patterns, and how long an overlay actually lasts
Thin overlays fail first where the load is hardest to predict: driveway aprons, garage entries, and anywhere a car turns its wheels while sitting still, which twists a thin surface layer more than straight-line traffic does. A well-prepared, properly cured overlay on a sound base slab can hold up for 10 to 15 years in a climate with 40 to 60 freeze-thaw cycles a winter and regular road salt. Skipped prep or a marginal base can show delamination in under three years, and once an overlay lifts at an edge, water gets underneath and the peeling spreads.
Doing the arithmetic before you decide
Resurfacing typically runs $3 to $10 per square foot depending on the system and how much surface preparation the old slab needs. Full replacement of a residential driveway runs closer to $8 to $16 per square foot once demolition, base repair, and disposal are figured in. On a 500 square foot driveway that is roughly $1,500 to $5,000 for an overlay against $4,000 to $8,000 for a full replacement. That comparison only holds if the overlay is going onto a slab that actually qualifies for it — spending $3,000 twice, once now and again in four years when an underlying crack reopens, costs more than spending $6,000 once and being done. A read on the base is worth getting before either number gets spent; the American Concrete Institute publishes guidance on evaluating existing concrete before any repair or resurfacing decision.
Frequently asked questions
Can you resurface over a crack instead of fixing it first? Only if the crack is stable and narrow enough to route and fill before the overlay goes down; an active or widening crack will telegraph through almost any overlay system within a season or two.
How do you tell if a slab is stable enough to resurface? Sound the surface for hollow spots, check for rocking underfoot, and monitor any existing cracks for several weeks — if the width or the vertical offset changes, the ground below is still moving and resurfacing is premature. See when a slab can be repaired and when it has to come out for the fuller checklist.
Does resurfacing add much thickness to the driveway? Most bonded overlay systems add somewhere between 1/4 inch and 1-1/2 inch, which is usually enough to account for at door thresholds and garage transitions but not enough to change grade or drainage in any meaningful way.