Concrete Repair Before You Coat
The Floor Is Only as Good as What It Bonds To
Epoxy is a coating, not a cure. It bonds chemically and mechanically to the concrete beneath it, which means every flaw in that concrete becomes a flaw in the finished floor — a crack telegraphs through, a contaminated patch refuses to bond, a weak surface lets the whole coating peel away with it. In Ghana’s humidity the stakes are higher still, because the slab is also the source of the moisture that lifts coatings. This is why the substrate work done before the resin is what actually decides the floor. Here is what that work involves.
Reading the Slab First
Before any repair, the slab is assessed for four things:
- Moisture — in-situ relative humidity to ASTM F2170 and moisture-vapour emission to ASTM F1869. In Ghana this is the failure wedge: an untested slab is the number-one cause of blistering and delamination.
- Strength and soundness — hollow, weak or friable concrete will not hold a coating no matter how well it is laid.
- Cracks and joints — their type and movement determine the repair method.
- Contamination — oils, curing compounds, paints and laitance all prevent bonding and must come off.
The Repairs That Come Before Resin
Crack and joint repair
Static cracks are routed out and filled with a resin or repair mortar so they do not telegraph through; moving joints are treated to accommodate movement rather than fight it. A crack coated over without repair simply reappears in the new floor.
Spall and pit repair
Spalled, pitted or eroded areas are cut back to sound concrete and rebuilt with a repair mortar to a level, sound base — so the coating has continuous, uniform concrete to bond to.
Surface preparation to ICRI CSP
Diamond grinding or shot-blasting removes laitance, oils, old coatings and curing compounds and establishes the specified ICRI concrete surface profile (CSP) — the mechanical key the resin bonds into. Concrete is profiled to ICRI CSP, not to a steel-only standard; getting the profile right is what lets adhesion pass ASTM D3359 at handover.
Moisture remediation
Where the slab reads high, a vapour-suppression primer or remediation layer is specified to the reading before the system goes down — the step that actually prevents the failure.
This is the discipline of concrete repair and substrate prep, and it is the foundation under every industrial epoxy floor coating we install.
Why Skipping It Is False Economy
A quote that goes straight to “clean and coat” is cheaper on paper and more expensive in reality. The crack reappears, the contaminated patch peels, the untested slab blisters — and the remedy is to grind it all off and start again, having paid twice. The substrate work is not an add-on to the floor; it is the floor’s durability.
The Bottom Line
Test the slab, fix the concrete, profile it to ICRI CSP, and remediate the moisture — then coat. Done in that order, a floor lasts 10–15+ years. Done out of order, it fails in one. The resin is the easy part; the substrate is the engineering.
Book a substrate assessment before you coat: +233 23 063 0004.