Delamination is when a coating loses its grip on the concrete and comes away in sheets or patches. It looks dramatic, and homeowners often assume they got a bad product. Almost always, the product was fine and the bond was compromised before the coating ever cured.
There are five common causes. Each leaves a recognizable signature.
1. Surface Contamination
What it looks like: the coating peels cleanly, and the underside is smooth. Flip a piece over and you see the coating's own surface, not concrete stuck to it. The slab underneath looks untouched.
What happened: something was between the coating and the concrete. The usual suspects are a cure-and-seal compound applied when the house was built, an old sealer, oil that soaked in over years, or tire dressing and de-icer residue.
This is the most common failure we are called to fix, and it is entirely a preparation issue. Chemical etching does not remove sealers reliably. Diamond grinding does, because it removes the top layer of concrete itself rather than trying to react with it.
Oil is a special case. It does not sit on the surface, it migrates into the pore structure, and it can be centimetres deep under a spot where a vehicle leaked for years. Degreasing helps; sometimes the contaminated concrete has to be ground deeper or, in bad cases, cut out.
2. Moisture Vapour Transmission
What it looks like: blisters or bubbles, usually in the field of the slab rather than the edges. Popping one reveals a damp, sometimes chalky surface underneath. Failures appear months after install, often the first spring.
What happened: water vapour moving up through the slab could not escape. Pressure built at the bond line until it pushed the film off.
Most Calgary garage slabs are on grade, and older ones frequently have no vapour barrier beneath. Ground moisture rises continuously. A moisture barrier primer is designed to manage this; without one, the coating is a lid on a slab that is still breathing.
You can test for it before any work happens: tape a square of plastic sheet to the slab, seal all four edges, wait 24 to 48 hours, and look for condensation. It costs nothing and it predicts a great deal.
3. Inadequate Surface Profile
What it looks like: the coating comes off in sheets with thin concrete dust on the back, and the exposed slab feels smooth, almost polished.
What happened: there was nothing for the coating to key into. A power-trowelled garage slab has a dense, closed surface. Coatings do not bond chemically to concrete; they bond mechanically, into an open profile.
The industry measures this as a concrete surface profile, and coating manufacturers specify a minimum for their products. Diamond grinding produces it consistently. Acid etching produces something much shallower and unevenly, particularly on a hard-trowelled or partially sealed floor.
There is a full comparison in diamond grinding vs acid etching.
4. Missed Recoat Windows
What it looks like: the layers separate from each other rather than from the slab. The primer is still stuck to the concrete; the top coat peeled off the primer.
What happened: the next coat went on outside the manufacturer's recoat window. Every coating has a period during which the next layer will chemically bond into it. Apply too late and the previous coat has fully cured — the new layer sits on top rather than bonding in.
Polyaspartic cures fast, which is what allows a one-day install, but it also means the windows are tight and the crew has to work to a schedule. This failure mode is a workmanship issue, not a materials one, and it is a reason to be sceptical of a crew that seems to be working slowly or leaving a floor half done overnight.
Dust settling between coats does the same thing. So does condensation forming on a cold slab between layers.
5. Thermal Shock and Hot Tire Pickup
What it looks like: circular or tire-shaped patches lifting, usually in the parking area, usually within the first year.
What happened: a warm tire sat on a coating that had not reached full cure, or on a system whose top coat softens under heat. As the tire cooled it contracted and pulled the coating with it.
Calgary makes this worse than most places. A vehicle comes in with tires warm from the highway onto a slab that may be near freezing. That temperature differential is exactly the stress case.
Two things prevent it: a top coat rated for it, and respecting the cure schedule. Our system takes foot traffic the next morning and vehicles after about 24 hours — driving on it early is a genuine risk, not a formality.
Diagnosing Your Own Floor
If you have a failing coating, pull up a loose piece and look at the back:
| What you see on the underside | Likely cause |
|---|---|
| Smooth, clean coating surface | Contamination or sealer |
| Damp, chalky concrete dust | Moisture transmission |
| Thin, even concrete dust; slab feels polished | Inadequate profile |
| Another layer of coating | Missed recoat window |
| Localized round patches only | Hot tire / thermal shock |
That diagnosis matters, because the fix differs. A profile or contamination problem means full removal and regrinding. A moisture problem means the same plus a different primer specification. A localized hot tire failure can sometimes be repaired in place.
What Prevents All Five
There is no clever product that compensates for skipped preparation. What prevents delamination is unglamorous:
- Diamond grinding to an open, uniform profile
- Moisture testing, then a primer that matches the result
- A clean slab immediately before each coat
- Respecting recoat windows
- A full cure before vehicles return
That is our whole process: diamond grinding, moisture barrier primer, 100% flake broadcast, UV-stable polyaspartic top coat, in one day, backed by a 5-year warranty. The warranty term is a deliberate choice — several Calgary companies advertise 15 or 20 years, and we would rather commit to a period we will service on every floor.
If you are getting quotes, the questions worth asking will tell you quickly whether a company treats these as fundamentals or as upsells. And if your current floor is failing, our cost guide explains how removal of an old coating affects the price.
