Used in patios, walkways, and full building structures, concrete is one of the most versatile materials in the world. Versatile, durable, and easy to apply and maintain, it’s no wonder concrete coating is such popular technique. However, it can be prone to developing cracks due to its porousness and might not perform well under certain conditions. If these problems are left unaddressed, they can lead to more dangerous hazards over time. To avoid cracking and collapsing, consider the following concrete coating methods for your concrete structure.
Polyurethane and Polyurea
These coating systems have been around for over 70 years and can protect concrete coating from the detrimental effects of moisture, corrosion, abrasion, and strong chemicals. However, polyurethane tends to blister if applied below temperatures of 32F or in humid areas. If so, you might find water, acids, chemicals, and other foreign materials to seep into your structure. To combat these issues, polyurea sprays were manufactured to withstand humidity and extremely low temperatures (as low as -20F).
Polyurea spray is particularly suited to construction projects such as roofing, parking areas, and bridges, where circumstances may change on a daily basis. To ensure maximum efficiency, spray equipment now comes in various temperature settings, variable-ratio settings, and are equipped with precise meter reading features.
Though polyurea sprays cure within 15 seconds, their incredible speed can sometimes hamper how well the spray adheres to the concrete. Because high curing speeds don’t necessarily allow coatings to be fully absorbed into cracks and crevices, multi-coat systems are a must. Epoxy-based primers first fill the porous concrete coating surface, which then bond quick-setting polyurea sprays. The primer also suppresses moisture and keeps air bubbles from forming.
Depending on your specifications, some structures may need a second polyurea coat to fill cracks, holidays, and pinholes, and a top coat to ensure color stability and UV protection in concrete coating. Multi-coat systems ensure that a structure is fast-reacting, resistant to water damage, and low-temperature curing.
The San Mateo-Hayward Bridge Expansion
To get a better grasp of the properties of multi-coat systems, take a look at the San Mateo-Hayward Bridge expansion project. To safely expand much-needed lanes, the California Department of Transportation (Caltrans) needed to come up with a 60-mil coating system to account for 3.2 million square feet of cast concrete. It also needed to withstand California humidity and have approximate longevity of 125 years.
Thanks to a three-layer coating system that incorporated an epoxy primer, an intermediate high-build spray, and an aliphatic top coat, the San Mateo-Hayward Bridge widening project was completed ahead of schedule. Its coating allowed for excellent chemical resistance and thermal and color stability. Thanks to the project’s success, many in the construction industry are now understanding the beneficial properties of polyurea coating systems.
Because concrete coatings can experience problems such as cracks and crumbling if subject to water damage or other environmental factors, builders have since incorporated polyurea multi-coat systems as a quick and simple solution. If your residential or commercial project is in need of a spray polyurethane foam solution, look no further than American Foam Experts. Our premium services come with a 15-year warranty that will guarantee your satisfaction for as long as you’re in your home.