Similar to other urethane coatings, Moisture-Cure Urethane coatings (MCU) are specialized coating solutions for a range of applications. They are excellent as durable coatings for damp surfaces, including water tanks. You can use MCU coatings for in-service water tank painting, which means you don’t have to drain your tank completely to apply the coating — translating to minimal downtime for your operations.
If you’re looking for downtime-minimizing coating solutions, choosing MCU for various projects can be an invaluable option to reduce costs. Expert contractors, like those from Raider Painting, offer easy-to-apply industrial tank coating and floor solutions, which saves you money and time.
In this guide, we’ll explore the properties and benefits of using moisture-cure urethane (MCU) and its applications in wet environments. We’ll also explain why this solution is a popular choice for facilities and structures that are never completely moisture-free, such as marine structures and water pipes.
What Is Moisture-Cure Urethane, and How Is It Different From Other Floor and Tank Coatings?
MCU is a specialized polyurethane coating that cures when it comes in contact with atmospheric moisture. Its formulation contains foundational isocyanate groups of atoms that react to hydrogen compounds, such as condensation on exterior surfaces. For this reason, moisture-cure urethane for water tanks and floors has become a popular cost-saving option for various industries.
MCU cures above 35 degrees Fahrenheit, with a slower curing reaction at lower temperatures. However, it is still possible to cure this material even at 20 degrees Fahrenheit requiring extended times.
Unlike other floor coatings such as epoxy or acrylic, MCU relies on humidity for curing. This property makes it highly effective in environments where controlling moisture can be quite a challenge. In addition, once it cures, MCU exhibits exceptional resistance to abrasion, chemicals, and weathering.
Furthermore, MCUs form a flexible yet durable coating that can expand and contract with substrates. This property reduces cracking and peeling compared to rigid alternatives like epoxy. Facility managers opt for this solution because it is tolerable to environmental factors.
Due to its effectiveness, the American Water Works Association (AWWA) has granted this solution the AWWA D102-03 Industry Standard for outside coating applications. It’s easy to apply, quick-drying, flexible, and durable, which allows for many industrial applications.
What Are the Key Benefits of Using Moisture-Cure Urethane for Industrial and Commercial Floors?
Many commercial and industrial areas are prone to high humidity. Some industrial spaces may also experience accidental chemical spills during operations, while other surfaces may be exposed to extreme temperatures. The properties of MCU make it ideal for these conditions, offering a range of benefits, which include the following:
- Superior Durability: As mentioned, MCU forms a durable and flexible barrier when it comes in contact with hydrogen compounds. This barrier can withstand the harshest conditions, including heavy machinery, forklifts, equipment, material traffic, and constant foot traffic. This coating can also exhibit elastic properties, which allow it to absorb impacts and resist cracking.
- Chemical Resistance: In many applications, an intermediate coat mixture containing micaceous iron oxide (MIO) is applied before using MCU. This double-layer coating improves chemical resistance and prevents damage from corrosive substances, oils, and solvents. MCU provides an impermeable shield that retains its structural integrity compared to other coating solutions.
- Exceptional Moisture Tolerance: As described earlier, MCU is an excellent option for high-humidity environments. Its curing process allows for a seamless application, which works quite well to achieve a durable and even finish. It can be applied to surfaces with residual moisture, whereas other coatings may have compromised adhesion, making it a viable option where thorough surface preparation may not always be feasible.
- Long-Lasting UV Resistance: Many traditional coatings, such as epoxies or standard paints, can chalk, fade, or discolor over time when exposed to prolonged sunlight. In contrast, MCU is designed to maintain its intrinsic properties despite prolonged UV exposure. This feature makes it a reliable choice for many outdoor applications, such as parking structures, rooftop facilities, driveways, exterior tanks, and loading docks.
- Effortless Application: This coating’s moisture-activated curing makes it highly adaptable to various environmental conditions, significantly reducing the complexities typically associated with coating applications. It works well on outdoor facilities where weather can be unpredictable or in locations with minimal environmental control.
How Does MCU Improve the Durability of Floors in High-Traffic Areas?
Upon curing, MCU creates abrasion-resistant surfaces. It can handle the stress of heavy machinery, carts, forklifts, and constant foot traffic without significant wear. With its high adhesion properties, the coating remains intact even under frequent use.
Why Is MCU Ideal for Areas With High Humidity or Moisture Exposure?
Unlike other coatings that may fail or bubble in wet conditions, MCU forms a strong, seamless bond with the substrate, even when applied in less-than-ideal surface conditions. As explained earlier, its curing process is highly reactive to hydrogen compounds, including moisture in the air. Expect some outgassing when large amounts of surface moisture accumulate during a coating application. Pinhole formations occur during outgassing when the moisture trapped under the MCU coating escapes. However, pinholes on the affected areas can be easily scraped off, removing all surface damage and creating a durable finish.
How Does MCU Perform in Extreme Temperatures Compared to Other Coatings?
This type of coating can maintain its integrity across a broad range of temperatures, making it suitable for environments with extreme heat or cold. Compared to epoxy coatings, MCU doesn’t become brittle when the temperature drops or softens in high-heat environments. The coating will also maintain its adhesion and flexibility, which prevents surface coatings from cracking or peeling. This feature allows applications in cold storage facilities, outdoor spaces, and areas with fluctuating temperatures.
Can MCU Be Applied to Both Concrete and Wood Surfaces?
Yes, apart from concrete and metal, moisture-cure urethane coatings can be applied to wood surfaces as well. Its excellent adhesion properties make it effective for sealing porous surfaces, which can help improve the aesthetics and durability of wooden substrates.
What Industries Benefit Most From Using This Type of Coating on Their Floors?
Given its features and characteristics, MCU coats have a wide range of applications across industries, which include the following:
- Manufacturing Facilities: Manufacturing floors are constantly exposed to heavy machinery, chemical spills, and abrasive materials. Applying MCU coatings prevents the degradation of assembly lines, chemical processing zones, and storage areas for raw materials. Facilities with heavy machinery can rely on MCU coatings to maintain safe and functional workspaces while minimizing maintenance disruptions.
- Retail Spaces: These establishments require flooring solutions that balance aesthetics with durability to withstand heavy foot traffic and enhance customer experience. MCU applications provide a sleek, polished appearance while resisting scratches, scuffs, and wear from shopping carts or strollers. In addition, its UV resistance ensures that the floors in retail spaces with large glass windows or skylights retain their vibrant color and finish over time.
- Warehouses and Distribution Centers: MCU coatings create a tough, seamless surface that withstands the daily grind of heavy machinery and the constant movement of goods caused by forklifts, pallet jacks, and heavy loads. Since they are moisture resistant, they are an excellent option for refrigerated storage areas or warehouses exposed to humidity.
- Hospitality and Food Processing: Commercial kitchens, hotels, restaurants, and food processing plants have unique flooring needs. MCU coatings are ideal for these facilities where water and liquids are frequently spilled, such as kitchen prep areas or dishwashing stations. Its non-porous finish prevents bacteria or mold growth, ensuring hygienic conditions for these establishments.
What Are the Maintenance Requirements for Floors Coated With MCU?
Floors coated with MCU are low maintenance and require simple cleaning routines to retain their appearance and functionality. Regular sweeping and mopping with non-abrasive cleaning solutions are sufficient to remove dirt and grime. You may schedule periodic inspections to help identify minor scratches or wear. These issues can be easily repaired with simple touch-ups by seasoned contractors.
How Does It Contribute to a Safer, More Slip-Resistant Floor Surface?
When you work with expert contractors, they can recommend the addition of aggregates, additives or textured finishes to MCU coatings to enhance slip resistance and reduce the risk of accidents in high-traffic or wet areas. Furthermore, its ability to maintain a seamless, non-porous surface prevents water penetration and reduces the likelihood of pooling. These properties make MCUs suitable for environments such as hospitals, commercial kitchens, and industrial sites.
What Are the Long-Term Cost Savings Associated With Using MCU Coatings in Commercial or Industrial Settings?
The durable nature of moisture-cure urethane coatings reduces the need for repairs or recoating, which helps to minimize downtime and operational disruptions. The longevity of MCU coatings varies based on factors such as application quality, environmental conditions, and maintenance practices. When properly applied and maintained, MCU coatings can provide durable protection for many years, reducing costs in the long run.
Trust Experienced MCU Specialists
With over 30 years of experience, Raider Painting has been a trusted partner for businesses across industries, delivering tailored coating solutions that stand the test of time. Trust our team to elevate the aesthetics and functionality of your commercial and industrial spaces with our proven expertise and top-notch solutions. Contact us today and leverage our extensive experience for your next project.
