ConcreteresurfacingandoverlayinAdelaide
A decorative overlay on a 60m2 existing driveway runs $4,500 to $8,500 in Adelaide. Half to two-thirds the cost of a full replace, when the substrate is sound. We connect you with concreters who assess before they quote.
Substrate assessment: the step most concreters skip
Resurfacing fails when the overlay is bonded over a cracking substrate. The cracks telegraph through the overlay within weeks to months. Customers find out after the money is spent and the overlay has failed in the same pattern as the old surface underneath.
The correct process is substrate assessment first. A network concreter inspects the existing slab, identifies whether cracks are shrinkage (cosmetic) or structural (load-bearing failure), tests bonding of any existing sealer, and checks slab thickness in at least 2 locations by coring or ground-penetrating radar.
If the substrate qualifies, the overlay quote follows. If it does not, the concreter recommends full replace and explains why. That recommendation protects you from spending on an overlay that fails at 6 months.
When to overlay vs when to replace
Overlay is right when: the existing slab is full thickness (100mm minimum), structurally sound, has only surface deterioration (spalling, staining, minor shrinkage cracks along control joints), and the slab level does not need to change (no trip hazards at the doorstep or boundary).
Replace is right when: the slab has structural cracks (3mm or wider, running diagonally, or showing step at the crack edge), the slab is settling unevenly, the thickness is below minimum, or the existing slab level creates a hazard that an overlay would worsen.
The cost saving of overlay ($4,500 to $8,500) vs replace ($9,500 to $15,500 for the same 60m2) only applies when the substrate genuinely qualifies. Network concreters are direct about which option applies to your slab.
Related services and guides
Concrete repair - crack diagnosis and structural assessment.
Concrete removal - when the slab needs to come out before a fresh pour.
Decorative concrete cost Adelaide - overlay vs full replace cost comparison.