Nearly everybody who calls us says the word "epoxy". Almost nobody wants epoxy. What they want is a hard, glossy, flaked floor that is easy to clean, and for the last decade or so the way to get that has been polyurea underneath and polyaspartic on top.
This page explains the difference properly, because it changes what you should be paying and what you should expect.
What polyaspartic actually is
Polyaspartic is an aliphatic polyurea. Chemically it is a polyurea whose reaction speed has been slowed down enough to be workable, and whose molecular structure is aliphatic rather than aromatic. That second part is the whole point: aliphatic chemistry is UV-stable, which means it does not yellow or chalk in sunlight.
Raw polyurea cures in seconds, which makes it unusable by hand. The aspartic ester chemistry buys you a working window of minutes instead, which is why you can actually roll it onto a floor.
The three systems side by side
Epoxy
Two-part resin and hardener. Cures rigid and hard. Excellent adhesion and build, good chemical resistance, cheap over large areas. Its weaknesses matter more in a garage than in a factory: it cures over days rather than hours, it ambers under UV, it is brittle rather than flexible, and it is vulnerable to hot tyre pickup. It remains a sensible specification for interior industrial floors with no sunlight and no warm tyres, which is exactly where we still use it.
Polyurea
Fast-curing, flexible, high tensile strength, tolerant of a wider temperature range during application. Flexibility is what solves hot tyre pickup, because the coating moves rather than releasing. Aromatic polyureas are not UV-stable, so they go underneath rather than on top. This is the base coat on most residential work now.
Polyaspartic
UV-stable, so it goes on top. Cures fast enough to allow a same-day install. High abrasion resistance and good chemical resistance. More expensive per gallon than epoxy, applied thinner, and considerably less forgiving to install because the working window is short. That last point matters: polyaspartic punishes a slow or inexperienced crew, and a bad polyaspartic install looks worse than a bad epoxy one.
Why the combination beats either alone
A typical residential system is a pigmented polyurea base coat, vinyl flake broadcast into it while wet, then a clear polyaspartic topcoat over the top, sometimes two. You get the flexibility and adhesion of polyurea against the concrete, and the UV stability and abrasion resistance of polyaspartic where your feet and tyres are.
Total film thickness on a residential garage generally comes out somewhere in the 20 to 30 mil range depending on flake density. That is thicker than it sounds and it is what gives the floor its solid feel underfoot.
The one-day claim, examined honestly
It is true, with conditions. On a slab in reasonable condition, grinding, repair, base coat, broadcast, scrape and topcoat genuinely fit inside a working day, and you can walk on it that evening.
What cannot be compressed into that day: a slab that needs significant crack and spall repair, a floor with an old coating that has to come off, or a slab that has failed a moisture test and needs a mitigating primer. In those cases anyone promising one day is promising to skip something.
Cure to full chemical resistance takes several days regardless. Vehicles back at around 24 hours, rubber-backed mats later than that.
Where polyaspartic is the wrong choice
It is worth being clear about this, because it does not do everything.
On very large industrial areas, a high-build epoxy is usually better value and builds thickness more economically. In commercial kitchens and food processing, urethane cement handles thermal shock and aggressive chemistry that polyaspartic will not. On a slab with genuinely high moisture vapour emission, no fast system solves that on its own; the answer is a moisture-mitigating primer underneath whatever goes on top.
And on a badly prepared slab, polyaspartic fails exactly as fast as anything else. The chemistry does not compensate for the grinder.
What to ask whoever quotes you
Ask what goes down in each coat and in what order. A quote that says "epoxy floor" without naming a base and a topcoat is describing an outcome rather than a system.
Ask how the slab is being prepared. If the answer is acid etching rather than diamond grinding or shot blasting, that is the single biggest predictor of failure in this trade.
Ask about total film thickness in mils. It is a real number and a legitimate question.
Ask whether the topcoat is UV-stable, particularly if any daylight reaches the floor through a window or an open door.
Ask what happens if the slab turns out to be worse than it looked. A good answer is a defined process for stopping and re-quoting. A shrug is not.
Alabama conditions specifically
Two local factors push the choice toward polyaspartic. The first is UV: an open garage door in Birmingham means direct sun on the slab for a good part of the day for most of the year, and epoxy ambers under that. The second is temperature swing. An uninsulated garage here moves from near freezing on a January night to well over 40°C on an August afternoon, and concrete expands and contracts through that range. A flexible system rides it; a rigid one eventually cracks at the bond.
Humidity affects application rather than performance. Polyaspartic is moisture-sensitive while curing, so a crew installing during a July afternoon has a narrower window than the datasheet suggests. That is a scheduling problem, and it is one of the reasons this work is done properly in the morning.
If you want to see how this is applied on a specific floor, our garage floor coating page walks through the whole process step by step. For basements, where moisture testing comes first, see basement floor coating.
Common questions
Is polyaspartic just expensive epoxy?
No, it is a different resin family. Aliphatic polyurea rather than an epoxy resin. The practical differences are UV stability, flexibility and cure speed, and all three matter in a garage.
Why does everyone still say "epoxy" then?
Because that is what people search for. The word became the generic term for the whole category, the way people say Hoover for vacuum cleaner. We use it too, for the same reason.
Is it slippery?
A smooth topcoat is slippery when wet, like any glossy surface. Flake texture helps, and aggregate can be added to the topcoat where grip matters, which it does on slopes and anywhere a wet car comes in.
Can polyaspartic go over my existing epoxy?
Only if the existing coating is fully sound and properly abraded, and even then it is a compromise. If any of it is delaminating, all of it has to come off, because the new floor can only be as well attached as the old one is.
How long does it last?
Over a decade in a residential garage that was prepared properly. The variable is preparation, not the product.
Does it smell during installation?
Far less than solvent-based epoxy. Low odour is one of the practical reasons it took over interior residential work, particularly for basements.
Get a free quote
Tell us the space and roughly how big it is. We'll come measure it, and you get the scope and the price in writing.