Epoxy
Bonds strongly to prepared concrete and resists many chemicals. It is the usual primer under other floor systems.
Guide
Compare coating chemistries
A quick, qualitative way to see how the main families differ. Real products vary a lot, so treat this as a starting point and read the data sheet for anything you plan to use.
| Chemistry | Cure speed | Flexibility | Sunlight | Where it often shows up |
|---|---|---|---|---|
| Epoxy | Moderate | Low, hard and rigid | Can chalk or yellow outdoors | Primers, indoor floors, tank linings |
| Polyurethane | Moderate | Medium to high | Aliphatic grades hold color | Floor topcoats, roof coatings, sealants |
| Polyurea | Very fast | High | Aromatic grades change color | Roofs, containment, linings, truck beds |
| Polyaspartic | Fast | Medium | Generally holds color | Garage and showroom floors, topcoats |
| Acrylic | Fast to dry | Medium | Good outdoors | Roof coatings, sealers, decorative finishes |
| Silicone | Moderate | Very high | Good outdoors | Facade sealants, roof restoration |
| Cementitious | Slow | Low unless polymer modified | Unaffected | Basements, tanks, repair mortars |
Qualitative and general. Individual products can sit well outside these descriptions.
Polyurethane
A broad family. Some grades are tough floor topcoats, others are soft and stretchy enough for sealants and roof membranes.
Polyurea and polyaspartic
Polyurea sprays on and cures in seconds. Polyaspartic is a related chemistry that rolls on and gives a little more working time.
Acrylic
Water based and easy to apply. Common on roofs and as clear sealers, but not usually chosen for heavy chemical exposure.
Silicone
Stays flexible over a wide temperature range and handles sunlight well. Most coatings will not stick to it later.
Cementitious
Mineral based coatings and mortars that breathe and bond well to concrete. Polymer modified versions add some flexibility.