Most questions we get about epoxy and polyurethane flooring are about the topcoat — colour, finish, gloss level. But the step that actually determines whether a resin floor lasts five years or fifteen happens before any resin is mixed: surface preparation. A well-chosen system installed over a poorly prepared substrate will fail. A modest system installed over a properly prepared one will perform for years.
Why Plain Concrete Isn't Ready for Resin
Fresh or existing concrete almost always has a weak surface layer — laitance, curing compound residue, oil contamination, or a smooth, closed surface that resin can't mechanically key into. Resin systems bond to concrete primarily through mechanical adhesion into an open, sound surface profile, not by "sticking" to whatever is there. Skipping this step is the single most common cause of early resin floor failure.
Moisture Testing Comes First
Concrete slabs — especially newer ones, or slabs without a proper damp-proof membrane underneath — can hold moisture that migrates upward over time. If a resin coating is applied over a slab with excess moisture vapour, the trapped moisture can cause blistering, delamination, or a hazy, milky appearance in the cured floor months later. Moisture testing (relative humidity probes or surface moisture meters, depending on the system) should be carried out before committing to a system, and acceptable moisture limits vary by product — this must be confirmed against the specific Technical Finishes system's data sheet for your project, not assumed from a general rule of thumb.
Mechanical Preparation Methods
Once moisture is confirmed acceptable, the substrate is mechanically prepared to remove the weak surface layer and create a suitable profile for bonding:
Diamond Grinding
Uses diamond-segmented discs to grind away laitance and light contamination while flattening minor high spots. A common choice for most commercial and light industrial floors ahead of a resin coating.
Shot Blasting
Propels steel shot at the surface to profile the concrete and remove contamination, leaving an aggressively textured, highly mechanical profile. Often preferred for heavier industrial systems or where a stronger mechanical key is required.
Acid etching is generally not used ahead of industrial resin systems in Botswana — it doesn't remove surface contamination or laitance the way mechanical grinding does, and can leave a surface profile that's inconsistent across the floor.
Repairing Damaged Concrete Before Resin Goes Down
Worn, spalled, or uneven concrete usually needs a repair overlay before the resin system itself is applied. Technical Finishes' Solidscreed 90 (high-strength industrial overlay screed) and Solidscreed 400 (polymer-modified overlay for thicker builds) are used to resurface and reinstate damaged concrete, while Solidkote 110 is a wet-to-dry epoxy bonding agent used to bond new toppings or repairs to the existing slab. Trying to install a resin topcoat directly over a damaged or uneven substrate — without addressing the underlying concrete first — is one of the more expensive mistakes to fix after the fact.
Where the damage is more structural than cosmetic — spalling, corroded reinforcing steel, or larger-scale reinstatement rather than general wear — ABE's concrete repair range is also stocked and commonly used for this type of work. Not every product in that range is suited to a floor that will carry foot or vehicle traffic, so the specific product needs to be matched to the application by our technical team rather than assumed. Technical Finishes' own Solidscreed and Solidkote products remain the more straightforward choice directly under a Technical Finishes resin topcoat, since they're designed as one system — but if ABE's repair range is used first for structural-level damage, compatibility with the planned resin topcoat should be confirmed with Technical Finishes before proceeding.
What Happens When Prep Is Skipped
Floors installed over poorly prepared substrates typically show the same pattern of problems: delamination or peeling in isolated patches (often near doorways or high-moisture areas first), bubbling or pinholing in the cured coating, and a floor that looks fine for a few months before failing well ahead of its expected service life. If you're seeing any of these on an existing floor, our 5 signs your floor needs resurfacing article covers what to check.
Talk to Us Before You Choose a System
Substrate assessment and moisture testing should happen before a resin system is finalised — not after installation reveals a problem. We can help confirm what condition your slab is in and what preparation it needs, and work with Technical Finishes' documentation to specify the right system for your project.
Read our complete Resin & Epoxy Flooring guide →
Planning a Resin Flooring Project?
Talk to us about your substrate and we'll advise on preparation and system selection.