Polyurea & Polyaspartic Coatings
Various concrete coating product types exist in today’s market – they include epoxies, polyurethanes, polyureas and polyaspartics. However, the current buzz within the industry primarily revolves around polyurea and polyaspartic coatings. These coatings have quickly gained popularity among installers due to their rapid-cure properties and are often hailed as a cure-all solution, leading to widespread promotion of “1-day coating” systems. This has inadvertently resulted in some misunderstanding for homeowners and a profusion of poorly installed floor coatings along the way.
What Are Polyurea and Polyaspartic Coatings?
What are polyureas and polyaspartics and what benefits do they offer when used as coatings for your garage floor? Are they a desirable choice? And why is there such aggressive marketing for “1-day” applications?
Pure polyureas are a subgroup of polyurethanes. Like most liquid concrete coatings, polyureas are 2-component products (components A and B). Unlike other coating types, however, pure polyureas swiftly catalyze or ‘cure’ in seconds and produce a remarkably hard coating in less than five minutes. Because of this, pure polyureas typically require specialized tools, such as portable reactors, when used to coat truck beds, heavy machinery, and roofs, for example.
Polyaspartics are chemically different…they are modified polyureas called “aliphatic polyureas”. These coating products are produced as a result of the reaction between an aliphatic polyisocyanate and an aliphatic diamine – known as the polyaspartic ester. Sounds a bit complicated, right? Well, to put it more simply, think of a polyaspartic as a type of polyurea with a “slowed” curing rate…it doesn’t catalyze in seconds. The cure rate of a polyaspartic has been “slowed down” just enough to permit installers to apply these products with common tools like rollers or squeegees – there’s no need for sophisticated equipment. So, every polyaspartic coating is simply a modified polyurea.
Advantages of Polyureas & Polyaspartics
The primary benefits of utilizing polyurea polyaspartic coatings are their speed and adaptability to temperature. Unlike epoxies, these coating types can be applied in very low (and high) temperature conditions. And their fast-setting characteristics allow for a quick application process! Under specific circumstances (when the concrete’s moisture content is very low), these coatings can be installed in just one day with an expected “return-to-use” on the subsequent day.
Additional advantages of polyurea polyaspartic coatings include: resistance to UV rays (no discoloration); excellent resistance to impacts and wear & tear; extreme resistance to stains and chemicals (including hot-tire pick up if a high-quality polyaspartic is used)…and low to no VOCs. Needless to say, polyurea polyaspartics are great products…but they do have one Achilles heel.
The Drawback of Polyureas & Polyaspartics
Polyurea-polyaspartic coatings, despite their numerous advantages, have a significant limitation: they aren’t spec’d for direct-to-concrete application due to their inability to mitigate for high moisture conditions in concrete. In other words, these types of coatings shouldn’t be used as the initial (primer) coat over concrete.
Does concrete hold moisture? Yes, it does. Concrete is porous and moisture wicks upwards through its tiny pores in a process called moisture-vapor transmission (MVT for short). Over time, this occurrence can result in the buildup of hydrostatic pressures that in turn exert an upward force against the initial primer coat. A wafer-thin polyurea-polyaspartic (these coatings can’t be applied thickly) doesn’t resist elevated hydrostatic levels and are thus prone to delaminating.
Delamination can be a problem when polyurea polyaspartics are applied direct-to-concrete in the presence of medium to high concrete moisture content. Contractors who specialize in “1-day polyurea” coating systems know this. So, as a simple workaround, they don’t warrant their coatings against “moisture-related issues” (including high hydrostatic pressure). But “moisture-related issues” are the #1 reason for concrete coating failures! So, the guarantee is almost meaningless.
The image (and video below) shows an applied “1-day polyurea” coating that has fully delaminated from its concrete substrate. Observe how the layers have peeled away as if the coating was wallpaper! This illustrates why 1-day polyurea coating systems don’t warrant “moisture related issues”…because they can’t. The good news is that there is a proper way to install coatings that does mitigate for moisture.
So Why Install 1-Day Systems at All?
1-day contractors use rapid-setting polyurea polyaspartic product types for both the initial primer coat (direct-to-concrete) and the transparent top coat. They do this in order to meet their “1-day” installation commitment. But with concrete coatings, speed and quality don’t mix! If there’s moisture in your concrete and hydrostatic pressure builds over time, these coatings peel. Be very suspicious if your bidding contractor suggest a “1-day” coating without ever measuring the moisture in your concrete floor!
But why would a contractor install “1-day polyurea-polyaspartic” flooring if moisture in the concrete presents such problems? The answer is simple: it’s lucrative! 1-day polyurea-polyaspartic coatings use less product (…a thin primer coat and single thin topcoat). Moreover, they only need one day of work, so labor costs are low too!
The Truth About Coating Product Types: Each Has Pros and Cons
As initially stated in this piece, there exist several coating product types: epoxies, polyurethanes and polyurea-polyaspartics. Contrary to the claims made by “1-day” installers, every coating type possesses its pros and cons.
While it’s undeniable that polyurea-polyaspartic coatings are outstanding products, we must acknowledge the significant downside – they serve poorly as primers. Epoxy and polyurethane coatings are also exceptional; however, they have significant disadvantages too! Epoxies, for instance, tend to “yellow” or “fade” when exposed to sunlight and are prone to staining and lifting from tires. Using an epoxy as a topcoat on concrete exposed to sunlight would be a bad decision. However, a 100%-solids, moisture-mitigating epoxy is a superb primer coat. These products ensure thorough concrete penetration while mitigating for moisture (and high hydrostatic pressure)!
Building the Optimal Coating System
Each concrete space to be coated is unique. An interior basement (with no vehicular traffic) is a very different animal from a garage or exterior patio. Crafting the optimal, industrial-grade coating system (a coating “system” is made up of several coating layers, often using different coating types) obliges the contractor to leverage the superior characteristics of each coating type!
We have shown that a 100%-solids, moisture-resistant epoxy is the most effective primer coat under moderate to high concrete moisture conditions. We have also shown that a quick-curing polyurea polyaspartic coating is an effective clear topcoat with its high UV, impact and stain-resistance properties. In garages, where the concrete can have significant moisture-vapor transmission (MVT), coupled with exposure to UV light and chemical staining from automotive fluids and hot tires, the perfect coating system would use a 100%-solids epoxy as primer and clear polyaspartic topcoat.
Contractors who specialize in “1-day polyurea” coatings are well aware of this. However, the lure of speedy-curing systems is hard to resist. What’s their solution? Provide a long-term or lifetime warranty to the customer but exclude “moisture-related issues” (like hydrostatic pressure) within the small print. If and when delamination occurs with the installed 1-day system, invoke the warranty exclusion!
We Do It Right the First Time
There’s an expression that says: “If you don’t have the time to do it right the first time, when will you have the time to do it over?”. Expert installers specializing in concrete floor coatings are equipped with an array of product types, including epoxies, polyurethanes …and polyurea polyaspartics. They aren’t confined to quick-cure products only, so they can leverage the superior characteristics of each coating type.
In the incredibly saturated market for concrete coatings today, GarageFloorCoating.com (Tucson) has encountered numerous “1-day” service providers and DIY enthusiasts who, unfortunately, install subpar concrete flooring solutions. It doesn’t need to be like this.
Our specialty lies in the installation of commercial-grade concrete floor coatings. Our garage floor coating systems take 2 days to install and we deliberately steer clear from using polyurea polyaspartic coatings direct-to-concrete (despite having the coating products to do so). We just won’t gamble with your concrete floor coating.
Simply stated…quality flooring takes a little more time.