For 25 years, Concrete Decor has promoted products that impart color and texture to concrete. Editorially, the magazine’s focus on quality workmanship rewards product manufacturers and those who use the product for their tireless efforts to improve and maintain quality standards.
Today, as a result, new and old concrete surfaces have grabbed people’s attention because decorative concrete demonstrates its ability to mimic the look of other building materials. It also imparts finishes that were previously unique to those other building solutions. This is where sustainability in the concrete industry has blossomed and where it may struggle to maintain that disposition in the future.
Ready-mix concrete changes
Concrete remains the undisputed world’s best and most used building material. However, the industry is seeing unprecedented pressure from environmental agencies to lower concrete’s carbon footprint.
In 2024, all 50 state Departments of Transportation approved the use of portland-limestone cement (PLC). This change has reduced the industry’s carbon footprint by up to 10%. Unfortunately, little can be said about Type 1L’s ability to improve the strength of concrete or the finishes consumers have come to expect from concrete.
Producers of chemical admixtures for concrete are bridging these changes with new additives for ready-mix concrete so contractors can meet their customers’ expectations of color, finish, and durability.
Choosing the right concrete finishes
Recently, a design/build contractor and his wife contacted Concrete Decor to ask about integral coloring for the concrete they planned to use for their home construction project. Learning more about their desire to achieve a matching color, indoors and outside, the conversation led to more in-depth discussions
about concrete finishes and their influences on color.
Ryan and Eva Dejesus’s home lies in the uppermost elevation of Nevada City, California, where winters are very cold and snowfalls can reach more than 6 feet deep. Although the interior floors would be poured in between existing exterior Faswall ICF walls, insulated from below, and heated with hydronics, the exterior surfaces would not. Subsequently, they needed a concrete finish that would hold up to snow chains, studded tires, occasional snowplows, and freeze/thaw cycles. The surface needed to be safe to walk and drive on and easy to maintain too. All of those criteria would influence the color of their concrete.
The bigger and more immediate question was whether an integral concrete color used for the concrete outdoors could make a successful transition indoors. Without mock-ups in place, and a goal to avoid the use of topical concrete coloring products, the desire for a uniform color was starting to wrestle with other project priorities. Ultimately, the couple decided to stick with natural gray tones.
Searching for contractor and mix design
The search for a reputable concrete contractor had been set in motion some months earlier, but busy early-summer contractor schedules presented problems for the Dejesuses. They once again reached out to Bent Mikkelsen at Concrete Decor about helping them find someone who could do this work for them. They knew a discussion about the concrete finish was critical for them to choose the best contractor for their project.
While the search for a contractor was underway, Dejesus started talking to the local ready-mix suppliers about mix designs and, in particular, the mix design the city used. He reasoned that local authorities would have stringent guidelines in place for public works projects given the readymix producers’ sources for cement, sand, and aggregate. This included Type 1L concrete, which contains a higher percentage of raw limestone than Type 1 and Type 2 and requires more controlled hydration.
The Dejesuses were adamant they didn’t want glossy polished concrete floors inside. Instead, they wanted floors with a matte finish, ones that wouldn’t be prone to random cracking and would be dog friendly. Oh, and yes, they wanted the concrete to reflect a level of craftsmanship that was evident in every aspect of this home construction project.
With the city’s concrete mix design in hand, the Dejesuses now had a target in sight. The next question was, could that mix design meet their needs? It was here that the products of E5 Nano Silica came into focus.
Concrete Decor’s Mikkelsen introduced the Dejesuses to E5’s technical representative and chief operating officer, Ben Shetterley, to help them better understand the impact of using E5 Internal Cure and Liquid Fly Ash. This resulted in some surprising changes to the mix design. The conversations also helped them understand how the products would impact the concrete as a finished floor in their home.
Their ability to improve concrete hydration and curing while reducing the amount of cement sounded promising.
“By controlling hydration and densification through the use of nanoparticles, E5 is able to consistently achieve reduced risk while improving aesthetic qualities and consistency,” Shetterley says.
Selecting the right contractor
While Ryan Dejesus focused on construction and making informed decisions about concrete, Concrete Decor made a few calls to some long-time contractor friends in the surrounding area. Once a few introductions were made, the Dejesuses decided on Bay Area retiree, Lee Levig. Mikkelsen explained that regardless of whether Levig had experience working with concrete treated with E5 products, as an experienced contractor, he’d be able to read the concrete quickly and adjust finishing practices on the fly.
With a concrete contractor and ready-mix concrete scheduled, Ryan and his crew could now finish installing the hydronic system over the Viper II Vapor Barrier and EZ Floor’s RAZ Panel, a modular 2-inch EPS insulation board with raised knobs to route the PEX tubing. They installed Insulation Solutions half-inch Insul-Joint along perimeter walls at elevation to serve as a bond breaker and to hold the vapor barrier in place. With a couple of days to spare, rebar reinforcements were completed, seated over specially selected plastic chairs fitting the insulation board profile. The job was ready for concrete.
Installing the concrete
After a two-hour drive from the Bay Area, Levig and his crew arrived at the jobsite in the morning. As scheduled, the first truck arrived at 6 a.m. and backed up to a line pump and crew ready to get the work done.
Once the concrete started flowing and screeding was underway, the crewman on the float had no trouble keeping pace. After the fifth of seven truckloads were delivered, three crew members dropped back and started an initial pass on knee boards with trowels. They were quick to get into a rhythm, and after a third pass, the concrete was hands-off.
According to Levig, E5 didn’t require additional steps and was easy to implement. It also didn’t impact the concrete’s performance and his crew’s ability to get a flat, clean finish. And that they did! By 1 p.m. the crew had eaten lunch, packed up, and headed home to the Bay Area.
“Each pour on our project has been a learning experience, and this one, albeit one of if not the most important, went off without a hitch,” Ryan says. “Each team member aided with their experience and knowledge to quickly adapt to our specific conditions.”
“In the final weeks of preparation pre-pour, my wife and I had to be hands-off on another project part-time, and our long-time friend and colleague, Glenn Parman of GP Building Development, really came through to help make our pour deadline.”
Like traditional admixtures that improve workability and strength, the use of E5 Internal Cure works like a topical hardener/densifier.
“While the world is focused on sustainability, durability concerns go unnoticed,” Shetterley says. “This is where E5 performs to holistically treat the entire concrete matrix to not only improve durability but also to reduce risk during transit, finish, and daily use.”
Its ability to control hydration throughout the slab after placement also minimizes tension, he adds. The use of E5 Liquid Fly Ash decreases cement demand and, along with it, a decreased demand for water.
For Levig, the concrete’s workability was not compromised at all.
On the evening of the concrete installation, Ryan Dejesus wet the surface, which didn’t hurt but wasn’t necessary. Under roof and out of direct sunlight, the slab was already doing the job E5 products were designed to perform. A review with Levig and E5’s Shetterley on the placement of control joints reduced Dejesus’ planned saw cutting the next day. Indeed, it was a breath of fresh air for the relieved owners, whose preparation and planning had paid off.
“By controlling hydration and densification through the use of nanoparticles, E5 is able to consistently achieve reduced risk while improving aesthetic qualities and consistency,” Shetterley notes.
A week later the concrete was still showing signs of moisture, but there was no sign of random cracking anywhere.
A little DIY
Because available concrete polishing contractors were also difficult to find, the Dejesuses took this project upon themselves and selected their own polishing pads. “It’s not easy to recommend an abrasive when you don’t know what type of machine it’s being used with,” says Mikkelsen.
To that end, Ryan Dejesus chose to first use a low-speed floor buffer wet, outfitted with Malish Diamond Devil polishing pads, in two stages. “This method had the least impact on the trowel marks the Dejesuses wanted to safeguard while also preventing any exposure of fines (sand) in the concrete mix,” Mikkelsen says. “Let’s just say, they wanted to preserve the subtle trowel marks on the floor as a reminder of the workmanship they witnessed on that morning a few months ago.”
Next, they continued refinement with Americo Black Diamond pads in multiple grits.
Finally, they treated the floors with E5 Protect topical sealer and used a high-speed machine to burnish with Americo pads. “This stage of surface refinement was initially planned as a quick rental and a few days of work. Once curing began to take shape, we discovered numerous unforeseen batch plant contaminants that prompted further research and coordination to remedy while still trying to achieve our desired finish,” Ryan says.
“The combo of Bent, Ben, Lee, and Rick Lewis, a wonderful rep from Americo, proved to be the most supportive and dedicated resource that we leaned on heavily to produce excellent results.”
Given the sharp learning curve this effort created for the husband-and-wife team, the floors have achieved their goals. And while departure from the use of integral coloring was necessary, gray concrete did not disappoint.
“This section of our house build was unique. To most, they see concrete as a surface to build on, not a finished floor or an architectural feature. Our project focus has gone through many changes in our two-plus years of building—progressing to now encompass sustainability, longevity, low maintenance, energy efficiency, health, fire safety, and, of course, beauty.”
“So much thought and foresight were invested into our finished floor, as it is a final product and there’s no doing it over. We are very thankful to Bent and Concrete Decor for all their efforts in helping us realize our dream. What started as a simple phone inquiry about color turned into something
much more—new life-long friendships.”
Lingering Questions
While concrete is the undisputed world’s best and most-used building material and a common architectural finish for residential and commercial projects, questions remain. Are we truly winning the day with a widening array of cement alternatives?
Keep in mind, those alternatives originate somewhere, just like cement. Is the effort to replace portland cement actually achieving its goal? Is the race to complete a building project in the shortest
possible time ignoring the questions of long-term durability?
And is it not a goal to build structures that we look back on 50 years from today with pride because they’re not only withstanding everything that earth, wind, and fire can throw their way, but they are also
architecturally endowed to support a creative society for future generations?
Shop E5 Nano Silica Products
Offered by Concrete Decor Store
E5 Liquid Fly Ash - Admixture for Concrete
by E5 Nano Silica
E5 Internal Cure - Internal Curing Admixture
by E5 Nano Silica
