Coating Concrete: What You Need To Know
Updated: May 21
What To Expect
Concrete is undoubtedly one of the most extensively used construction materials worldwide. If you have concrete flooring, coating it may be a wise decision. But what exactly are concrete coatings, and are they really worth it? For the average homeowner or business owner, concrete coatings offer a range of benefits beyond just enhancing the look of your concrete. These coatings can improve the performance of your concrete and come in numerous options, each with its unique advantages. If you're curious about what to expect when it comes to concrete coatings, read on as we have everything you need to know outlined below.
Why Coat Your Concrete?
Coating your concrete offers two significant advantages. First and foremost, uncoated concrete is highly absorbent and susceptible to water damage. Over time, moisture can accumulate within the concrete, leading to cracks, loss of structural integrity, and corrosion. This can significantly shorten the service life of your concrete. Another disadvantage of uncoated concrete is its susceptibility to chemical damage. Although concrete is inherently resistant to UV light, exposure to chemicals in areas such as garages, commercial or industrial facilities can wear it down gradually. This leads to a reduction in service life, aesthetics, and overall performance of the concrete slab. By coating your concrete, you can protect it against both water and chemical damage, ensuring that it remains functional and aesthetically pleasing for years to come.
The Types Of Concrete Coating Systems
Concrete coating systems typically comprise repair compounds, sealants, and surface-applied toppings. While repair compounds are commonly used for concrete flooring, in this discussion, we will focus on the most prevalent form of coatings used in commercial and residential settings - surface-applied toppings and sealants such as epoxies, polyurethane, and acrylic sealers. Epoxy flooring, for instance, is a resinous coating made of an epoxy resin and a urethane hardener that creates a durable and chemical-resistant coating for your concrete. Urethane and acrylic sealers are also popular in residential and commercial settings since they are quick to install and provide protection from chemicals, wear, and a range of chemicals depending on the type of sealer used.
Unfortunately, the performance of the coating you apply to your concrete cannot always be predicted with absolute certainty. For this reason, tests are conducted to ensure that professional-grade materials can withstand the test of time on both commercial and residential slabs, where the conditions are not always simulated as they are in a lab. Below are some of the tests that are typically performed on coatings to determine their performance expectations.
ASTM D4587 (Standard Practice for Fluorescent UV-Condensation Exposures of Paint and Related Coatings) is a test used to determine the weatherability of specific coatings. In this test, coatings are applied onto a mortar pad and placed in a QUV cabinet, which simulates UV rays and humidity for a duration of up to 2500 hours or 15 weeks. The durability of the coating is then evaluated based on its resistance to blistering, total coating erosion, and color retention.
The same mortar panels used in the ASTM D4587 test are also subjected to warm and cold cycles to simulate the effects of freezing and thawing. These tests also involve intentionally introducing defects to evaluate the coating's reaction in certain scenarios. The testing process is rigorous and consists of rotations of 50, 150, and 300 cycle tests.
The Performance Of Epoxy Coatings
Epoxy coatings are highly effective in protecting concrete due to several reasons. Although they cannot provide absolute protection indefinitely, they do offer resistance to water and chemical damage by creating a seamless and non-porous finish that prevents moisture penetration. Additionally, epoxies are much stronger than conventional concrete, with a weight tolerance of up to 14,000 PSI, making them up to 7 times more resilient. As a result, they offer excellent protection against heavy usage of equipment, heavy storage and accidental dropping of objects.