Epoxy vs Polyurea Floor Coatings Explained (Pros, Cons, Applications, and More)
January 8th, 2024 | 4 min. read
Floor coatings play a crucial role in protecting and enhancing the durability of concrete surfaces, especially in high-traffic areas or industrial settings. Among the various options available, epoxy and polyurea floor coatings stand out, each with its own:
- Unique chemical composition
- Application Characteristics
- Performance attributes
This may lead you to wonder, “How are epoxies and polyurea concrete coatings different?” and “Which one is better?”
In this article, we'll answer these questions frankly and explore the differences between epoxy and polyurea floor coatings. We’ll also take a transparent deep dive into the application and performance of both types of coatings.
If you’re interested in the average cost of epoxy and polyurea, check out our separate article on that topic here.
- Chemical Composition:
Epoxy:
Epoxy coatings are typically formulated from a combination of epoxy resin and a hardening agent, which can be polyamine or polyamide. This chemical reaction results in a rigid, strong, and chemically resistant surface. The epoxy coating forms a cross-linked structure that provides excellent adhesion to concrete substrates.
Polyurea:
Polyurea coatings, on the other hand, are derived from the reaction between an isocyanate component and a resin blend containing amine-terminated compounds. This chemical composition imparts flexibility, rapid curing, and resistance to abrasion. They form a more elastomeric structure compared to the rigid nature of epoxy.
- Curing Time:
Epoxy:
Epoxy coatings generally have a longer curing time compared to polyurea. They may require several days (typically two) to fully cure and achieve their maximum hardness. This prolonged curing time allows for one additional benefit, though. The extended drying duration allows the epoxy more time to seep into the concrete and bond with it, enhancing adhesion.
If you have some hairline cracks and/or spalling, the epoxy curing process will level the floor out and hide damages. However, if the installation crew you contract is preparing your floor right, they will grind and sand the concrete to make it level. This will give your floor an optimal texture profile that a coating can easily grab onto.
If your concrete floor does not have a well-textured surface, any coating will have trouble adhering to it, which can make it easily peel off the substrate. This concrete preparation should be consistent between epoxy and polyurea applications.
Polyurea:
Polyurea coatings boast a much faster curing time, often drying within hours (usually 6 – 8). This rapid curing is advantageous for projects that demand a quick turnaround, making polyurea an attractive option for those with time-sensitive deadlines or if you need to access your garage again ASAP.
Although polyurea coatings can be applied and completely dry on the same day. If you need a moisture-vapor barrier installed, this will extend the time you can’t walk on your floor by a whole day.
- Application Temperature:
Polyurea:
Polyurea coatings exhibit greater versatility when it comes to temperature extremes. They can be applied in a broader range of humidity levels and temperatures, including colder conditions, providing flexibility in various climates.
Polyureas can be applied in very cold temperatures, down to -20 degrees Fahrenheit.
Epoxy:
Epoxy coatings may have limitations regarding application temperature. Some formulations may not be suitable for very low or high temperatures, impacting their versatility in certain environmental conditions. High humidity is also another factor that can cause many epoxies to cure too quickly and foam.
Epoxies do not fare well in cold weather especially. It needs to be at least 50 degrees or higher for an epoxy to cure in its usual timeframe. At 40 degrees or lower, epoxies will not cure at all.
We once talked to a customer living in New York whose garage floor was previously done with epoxy. He shared with us his horrible experience of having to wait 4 months to use his garage again. With the floor being too cold, it took that long for the epoxy to start the curing process. Epoxies aren’t made to cure in cold temperatures. This is why you’ll find more companies using epoxies in the southern United States.
- Flexibility:
Epoxy:
Epoxy coatings are known for being hard, rigid, and brittle. They are more prone to cracking if the substrate experiences movement or expansion/contraction.
Polyurea:
Polyurea coatings showcase superior flexibility and can withstand substrate movement without cracking. This characteristic makes them well-suited for environments where the substrate is subject to temperature fluctuations or structural movement.
- Adhesion to Substrate:
Epoxy:
Epoxy coatings typically exhibit strong adhesion to concrete substrates, forming a reliable bond that enhances durability.
Polyurea:
Polyurea coatings also provide excellent adhesion to concrete surfaces and may be more forgiving on improperly prepared substrates. This can be advantageous in scenarios where surface preparation is challenging.
- Chemical Resistance:
Epoxy:
Epoxy coatings offer good chemical resistance, making them suitable for areas exposed to various chemicals commonly found in industrial environments.
Polyurea:
Polyurea coatings are equally chemically resistant and can withstand exposure to a wide range of chemicals, providing a robust protective barrier against corrosive substances.
- UV Stability:
Epoxy:
Epoxy coatings will experience yellowing and degradation when exposed to prolonged UV radiation, impacting their appearance and longevity over time.
Polyurea:
Polyurea coatings are generally more UV resistant and less prone to yellowing or degradation from sunlight exposure. This makes them a more reliable choice for outdoor applications. However, the difference is not significant. Neither Epoxies nor polyurea are UV stable, meaning both will amber and break down from frequent sun exposure.
On the other hand, 100% polyaspartic coatings like our Floor Shield product are completely UV stable. We recommend going with a crew that offers polyaspartic coatings, especially for outdoor applications, such as backyard patios.
- Use Cases:
Epoxy:
Epoxy coatings are commonly employed in areas with moderate to heavy foot traffic, such as commercial and industrial settings. Their durability and chemical resistance make them suitable for large, demanding environments at a (typically) cheaper price per square foot.
Polyurea:
Polyurea coatings have better abrasion resistance than epoxies. This means that damage from impacts will not cause it to crack or break off as easily as epoxy. For an area with high vehicle traffic, like in a garage you frequently park in, polyurea might be the better option for longevity.
In general, epoxies break down quicker than polyureas. Most every polyurea-based concrete coating business will use a polyaspartic topcoat. They do this because polyaspartic coatings are more durable than most concrete coatings.
Epoxy topcoats are more varied. You’ll have installers put on a urethane topcoat, and other installers put on a polyaspartic. Most of the time, contractors will use urethane if the customer does not require flakes to be added. Only the polyaspartic topcoat can be applied thick enough to make a flake system work.
In Summary
The choice between epoxy and polyurea floor coatings depends on your specific project requirements and conditions. While epoxy coatings offer strong adhesion, chemical resistance, and are most of the time cheaper, polyurea coatings stand out with their:
- Flexibility
- Durability
- Rapid curing
- Performance in extreme weather.
In general, we recommend going with polyurea for most garages and outdoor applications because of the above benefits, while epoxy coatings are ideal for indoor applications such as basements or bathrooms because of their cost-effectiveness.
If you’re interested in learning about the other benefits polyaspartic coatings have over epoxies and polyureas, check out our breakdown here.
You can also scroll down to get a free, no-obligation quote from us at Floor Shield.
