Polyaspartic is a subtype of polyurea engineered for faster cure, better UV stability, and a clearer finish. In our Valence system, 100% solids polyurea is the basecoat (for bond and flexibility) and 85% solids polyaspartic is the topcoat (for UV, chemical, and scratch resistance). They're chemically related and work together as one system — not two competing products.
This is the question I get asked most after color and cost. Let me break it down without the chemistry lecture.
Are they the same thing?
Related, not identical. Polyurea is a broad family of two-component coatings that form when isocyanate reacts with an amine. Polyaspartic is a specific type of polyurea where the amine is aspartic acid ester — that one substitution changes the behavior in useful ways. So every polyaspartic is a polyurea, but not every polyurea is a polyaspartic.
If that sounds like hair-splitting, think of it like this: pickups and sedans are both cars. They share most of the same parts and engineering. But you'd put a different one in your driveway depending on what you need.
Why use polyurea as the basecoat?
Bond strength and elongation. Standard polyurea is the stronger structural coating. It soaks into the concrete profile (after diamond grinding) and locks in mechanically and chemically. Our Valence basecoat tests at 674 PSI bond strength — so strong that in pull tests, the concrete fails before the coating does. It also flexes at 311% elongation, which matters in freeze-thaw climates like Wisconsin where the slab moves.
Polyurea also cures through moisture, so it's more forgiving on slabs with higher moisture vapor emission rates. Up to 3 lbs / 1,000 sqft / 24 hr (ASTM F1869) is handled without issues. Epoxy struggles above 3 lbs; polyurea doesn't.
What polyurea doesn't do as well: UV stability. Pure polyurea can yellow over time in direct sunlight. That's fine for a basecoat — it's covered by flake and topcoat — but you don't want it on top.
Why polyaspartic on top?
UV stability, clarity, and faster cure. Polyaspartic is aliphatic, which means it doesn't yellow or chalk from UV exposure. Our topcoat carries a lifetime UV fade warranty. The polyaspartic topcoat also cures clearer than standard polyurea, which matters when you want the flake colors to pop instead of looking muddied.
Polyaspartic cures fast enough that we can apply the topcoat and be ready to walk on the floor overnight. That's what lets us do one-day installs.
It also handles UV exposure on patios, front porches, and anywhere else the floor sees direct sunlight. Patios and porches are actually a great application for this reason — you don't have to pick between a good bond and a surface that holds color.
Why not just use polyaspartic for the whole system?
You could, and some contractors do. Full polyaspartic systems exist. But they have tradeoffs:
- Less forgiving on moisture. Standard polyurea handles higher MVER better than polyaspartic.
- Thinner builds. Polyaspartic is typically lower solids, so you need more coats to get the same mil thickness.
- Cost. Polyaspartic is generally more expensive per gallon than polyurea.
- Pot life. Polyaspartic kicks fast once mixed — great for cure time, but it gives you a narrow working window on each batch.
Using polyurea for the base lets you get the bond strength and moisture tolerance where it matters, and polyaspartic on top where UV resistance and clarity matter. Best of both.
Why not just use polyurea for the whole system?
Yellowing. Pure aromatic polyurea yellows under UV. In a garage with the door closed most of the time, that's slow. On a sunny patio, it's noticeable within a year or two. The polyaspartic topcoat is how you get permanent color stability without giving up the benefits of the polyurea base.
It's also scratch resistance. The polyaspartic topcoat has 4x the abrasion resistance of epoxy by ASTM D4060, and better scratch resistance than bare polyurea. Putting it on top protects everything underneath.
How thick is each layer?
Rough numbers for a typical install:
- Polyurea basecoat: 8-12 mils
- Flake broadcast: embeds into the basecoat, adds some thickness
- Polyaspartic topcoat: 6-10 mils
- Total system: 15-25 mils
That's meaningfully thicker than DIY kits (1-3 mils) and noticeably thicker than bargain contractor jobs. More in how thick is polyurea.
Can I tell the difference between polyurea and polyaspartic installs?
Usually not visually on day one. Both look good when fresh. The differences show over time:
- An all-polyurea install will start yellowing in UV exposure within a year or two.
- An all-polyaspartic install may have thin spots and be more sensitive to substrate issues.
- A hybrid polyurea + polyaspartic install (like ours) holds color and bond for 15-25 years.
If you're getting quotes, ask what's in each layer. "We use polyurea" isn't enough — ask about the topcoat specifically. If it's the same polyurea as the base, that floor will yellow. If it's polyaspartic, it won't.
What about VOCs and smell?
Both are near-zero VOC. That's one of the other advantages over solvent-based epoxies. You can coat an attached garage without stinking up the house for a week. Cure smell is mild and clears within hours of the topcoat being rolled out. I've done plenty of attached garages where the homeowner stayed in the house all day and didn't notice anything.
What's the minimum application temperature?
Polyaspartic can go down to 30°F minimum. Epoxy needs 50°F minimum, sometimes higher. That's a big deal in Wisconsin, where a lot of unheated garages don't hit 50°F for half the year. Polyurea basecoat has similar cold tolerance, so we can install in conditions that would shut epoxy contractors down.
What about epoxy?
Different chemistry entirely. Epoxy uses an amine-epoxide reaction instead of isocyanate-amine. It's rigid, moisture-sensitive, slow-curing, and UV-unstable. I used to install epoxy and stopped because I got tired of the callbacks. Full comparison in polyurea vs epoxy.
Is Valence the only brand that does this?
No, but I think they do it best. Valence is based in Mendota Heights, MN, with a training center in Eagan where I got certified. I picked them because the polymer chemistry is real, the warranty is backed, and the local support means I can get material and tech help fast. I wrote more about why I chose Valence in why we use Valence coatings.
Got questions about the system for your specific floor? Get a free quote or call Dave at (715) 307-8302.