| Factor | Polyaspartic | Polyurea (aromatic) |
|---|---|---|
| Chemistry | Aliphatic polyurea | Aromatic polyurea |
| Working time | 20-40 minutes | 5 seconds - 10 minutes |
| Application | Roller or squeegee | Plural-component spray rig |
| UV stability | Excellent | Poor: yellows and chalks |
| Elongation | 50-150% | 100-400% |
| Build per coat | 4-10 mils | 10-40 mils |
| Best role | Wear and topcoat layer | Flexible base layer |
| Installed cost | $7-$12 / sq ft | $8-$15 / sq ft |
Cure speed changes who can install it
Aromatic polyurea can gel in seconds. That is a feature in industrial spray applications and a dealbreaker for a hand-applied residential floor: there is no time to backroll, no time to broadcast flake evenly, and no time to fix a holiday in the film.
Polyaspartic's tuned cure gives a crew a real working window while still allowing a same-day recoat. That single property is why the residential one-day install market runs on polyaspartic rather than straight polyurea.
UV stability is not negotiable outdoors
Aromatic polyurea will discolor under sunlight. On a warehouse interior, nobody cares. On a patio, pool deck, or a garage with the door open all afternoon, it is a visible failure within a season. Polyaspartic is aliphatic and holds its color.
Flexibility versus hardness
Polyurea's higher elongation lets it bridge and survive moving cracks and hard freeze-thaw cycling. Polyaspartic is harder and more abrasion resistant at the wear surface. This is why the strongest specifications use both: polyurea base for movement tolerance, polyaspartic top for wear and UV.
How to read a quote that says 'polyurea'
- Ask whether the material is aliphatic or aromatic: that determines UV behavior
- Ask whether it is spray or roller applied
- Ask what the topcoat is, specifically, not what the system is called
- Assume any hand-rolled 'polyurea' garage floor is really a polyaspartic
The verdict
For residential floors, polyaspartic is the answer: it is the only one of the two that can be hand applied and left in the sun.
Specify polyurea as a flexible base layer when the slab moves or takes impact, always under an aliphatic topcoat.