EcoTerra pavers are debuting in North America in Unilock’s Promenade Plank profile, 4- x 12- x 2.75-in., with shot-blast Revela surface and Light Steel Grey or Light Opal Blend colors. Commercial installations to date have included a residential driveway in Ontario, following a successful demonstration at Unilock’s Georgetown operation. In addition to face mixes with mineral binder, EcoTerra pavers also feature EnduraColor, whose two-step process ensures a refined surface and bright color. Water repellant properties curtail dirt and stain penetration.
Major hardscape unit producer Unilock is ushering a new, greener era with EcoTerra paving stones, whose face mixes are formulated with a carbon neutral, alkali-activated mineral binder. The mix design yields a highly durable, colorfast product with carbon metrics up to 15 percent below those of paving stones bearing portland cement face and base mixes. Presently molded at Unilock’s Georgetown, Ontario plant, the EcoTerra series responds to increasing attention to carbon metrics from the design community, municipalities and consumers. It also provides landscape contractors or hardscape installers an tool to differentiate their offerings from the competition.
An absence of portland cement enables the mineral binder to perform free of chemical reactions spawning efflorescence common in concrete masonry hardscape and building units. The binder evolved from concrete durability research & development under Metten Stein + Design, Germany. Unilock is seeking North American production of the material, but in the interim sourcing it from Europe.
Ahead of EcoTerra commercialization, Unilock tested the face mix binder performance per ASTM C936, Standard Specification for Solid Concrete Interlocking Paving Units, noting compressive strength of more than 12,000 psi, well above the standard’s 8,000 psi threshold. Tests also showed EcoTerra face mix absorption levels below a maximum 5 percent value. The product meets the requirements of ASTM C1645, Standard Test Method for Freeze-thaw and De-icing Salt Durability of Solid Concrete Interlocking Paving Units, which has a maximum mass loss of 225 grams/square meter at 28 cycles—essential for the cold climates throughout key Unilock markets. Bond strength between EcoTerra face and base mixes proved comparable to conventional concrete per CSA 23.1-19, Concrete Materials/Test Methods requirements.
“We’re excited to bring EcoTerra to the hardscape market as a part of our efforts to pave a greener way,” says Unilock Director of Sustainability Elaine Willis. “The world is focused on cutting carbon emissions, and this is just the first step in the evolution of concrete paver production. While the entire cement industry is working toward large scale, long term solutions that reduce carbon emissions throughout their value chain, we each need to do what we can, today. That’s why it’s so important for us to bring EcoTerra to market.”
Planning projects holistically—with a full system approach encompassing trees, plants, concrete, permeable paving systems and soil—makes it possible to create a living, breathing system that can contribute to a climate neutral or negative project, regardless of the embodied carbon value of the products within the system, she adds.
