Based near Seattle, Wash., Clark Branum has become one of the most respected voices in the decorative concrete finishing industry as a result of four decades of exemplary work. He currently runs his own contract company, Advanced Concrete Coatings, while also serving as technical director for SUNDEK Products and as a decorative concrete specialist for the American Society of Concrete Contractors (ASCC), where he functions as an industry liaison.
As part of an interview for CoatingsPro’s Concrete Covered supplement, which came out in December 2022, Branum spoke with us about a number of lessons learned from his career and trends in the marketplace. Read on for a partial Q&A of that conversation, and listen to the complete interview via the embedded podcast at the bottom of this article.
Q: How have coatings for decorative concrete changed relative to when you started in the business?
Branum: There’s always advancements in the chemistry, and that’s where I see the most changes. A lot of the standard finishes, some of them have been around for over 50 years. They’re just really well accepted and broadly used. You know, spray texture for pool decks has been around since the 1970s. That’s been a main staple in the coatings environment, and that’s still used today.
What I see is advancements in the technology, and advancements in the polymers. The actual work itself; it’s still nuts and bolts. Guys still have to go out and prep the concrete to do it correctly. They still have to prime. They still have to patch and do repairs, and create a good surface profile. And they still have to install the coatings the old-fashioned way. It hasn’t gone to any kind of automated sequence at this point, and I’m not sure that it ever will. I think that’s one of the things that attracts certain individuals to this type of work. It’s just not easy. Like the old adage says, if it was easy, everybody would do it. It’s challenging. And you have to deal with weather. You deal with temperatures.
One of the trends I’ve seen is polymers and chemistry that’s a bit more forgiving for different types of weather. We now have certain epoxies that are formulated for temperatures. If you have your application at a really high temperature, you can use a slower-setting epoxy. The standard [is for] temperatures around 70 °F [21.1 °C]. But also they have a cold formulation that allows you to work in colder climates at places where it gets around 40 °F [4.4 °C]. You should typically be at 40 or above for most coatings.
The other problem that we run into, as a contractor, is you have to wait a really long time for something to set up, or get hard, in those conditions. It could take 48 hours instead of the normal 12 hours, so we’re seeing some formulations recently in the last couple of years that allow you to choose a temperature range for your application.
Q: How much do regional differences change your application practices?
Branum: Well, if you’re going to work in the Seattle area, you have to become an amateur meteorologist. You have to keep a close eye on the weather. As long as it’s dry and above 40 °F, we can continue to work outside. But once we drop below our temperature, whether the weather’s nice or not, we pretty much lose our ability to bond coatings to concrete.
So we have to move indoors, and we can do a lot of surface preparation and shot blasting and stuff like that as well. That keeps us busy. We can do interior floors and covered things, we can do some polishing and microtopping, and overlays that can be done in the wintertime: chip floors, quartz floors, things like that.
During the summer, you have to manage that window. You have to watch the weather and be aware of it. If there’s days where you know it’s going to be wet, you go do something else, or you can do prep that day. But you can’t actually put the coating down.
The biggest challenge is you want to make sure that your coating has really good integrity and is able to bond. So you need a certain amount of dwell time for that material to chemically bond to the surface. Even in hot weather, that can be challenging. I’ve seen guys have failures when they were above 100 °F [37.8 °C]. The material literally sets too fast, and it can actually set before it’s able to bond to the substrate.
There’s a wet material sitting on the surface of the concrete, and it needs to seep in to a certain depth for it to create that chemical bond with the substrate via the primer, chemically or mechanically. But if it flashes and sets too fast, sometimes your primary can dry, and that becomes a bond breaker. So there’s some pitfalls there with hot weather as well as cold weather.
Q: What’s different about concrete coating jobs relative to any other substrate?
Branum: You need to know a little bit about the chemistry involved in a piece of concrete. It’s a living, breathing, growing thing. It moves, it cracks, it shrinks, it creeps, it crawls, it curls, and it does a lot of things. It reacts when it’s exposed to harsh environments. You have the potential for corrosion, you have ASR [alkali-silica reaction], you have a lot of things to deal with in concrete.
So attending these conferences and educational seminars that are available at World of Concrete or ASCC, these things really can improve a guy and really help him raise the bar… and become more aware of the substrate he’s working on.
I’ve seen a lot of people go in and want to polish floors. They’re painters, and sure, they might be great with a roller and a pail. But they don’t know anything about painting concrete and how the concrete is going to react to that paint, as well as what’s going to bond and what isn’t going to bond. And surface profiles, they’re hard to achieve with really hard surface concrete, whereas with soft concrete, they’re almost too easy to achieve. So, you have to modify what you’re doing a little bit.
But the biggest thing is learn the animal. Learn about concrete. Learn what makes it tick. Learn about the chemistry and the ingredients and how they react together and how they act over time. Learn the curing methods.
There’s a lot of things about concrete that can be learned. It takes a little time but the really good resources are out there. ASCC, ACI [American Concrete Institute], World of Concrete, the seminars… go down that seminar list and pick a few that you want to attend. The nice thing about ASCC and some of those organizations is that if you attend the conference, you can attend every seminar that’s there for free. Concrete Décor [magazine] has always been a good resource, as far as their decorative concrete event. There’s educational resources out there.
I would suggest that guys really go back and learn the basics of concrete, if you’re new to the business. Because everything you do is based on the concrete. A lot of times, the concrete can cause a failure… unless you get that foresight to be able to examine a piece of concrete and recognize a problem when you’re looking at it. When concrete has a crack, we look at it, right. But when I look at that, I try to figure out what caused it to crack. I ask, “Why did it crack there, and not everywhere else?” There’s usually a cause and effect, right? If you see a condition in the concrete, then you need to recognize that there’s a problem. Usually, you have to start by addressing that issue before you can possibly have any success with the coating.
The complete interview with Clark Branum can be listened to below, and more insight is available in CoatingsPro’s newly released Concrete Covered supplement. For more information, contact: Advanced Concrete Coatings, (425) 327-5628, www.adv-coatings.com.