Months ago we heard news of the “nation’s first carbon-positive hotel”—a 13-floor, 130-000-sf cement tower with a triangular layout and eye-shaped windows. Populus, designed by Studio Gang and developed by Urban Villages, broke ground in Denver, Colo., last year with plans to be operational by summer 2024. What makes Populus a carbon-positive project is a collection of variables, from minimizing waste to using fewer finish materials. But there’s one huge driver behind the green initiative: sustainable concrete.
ECOPact is an optimized, low-carbon concrete made from large amounts of supplementary cementitious materials (SCM). With lower embodied carbon content compared to conventional concrete, ECOPact aims to be an attractive alternative for sustainability-driven engineers.
Sustainable concrete: ECOPact
Designed by Holcim, a sustainable building materials supplier, ECOPact offers a low-carbon alternative that not only meets, but exceeds the properties of standard (CEM I) concrete. This allows the material to be used in all traditional applications: structural components like foundations, columns and beams; to walls, driveways, bridges, and more.
ECOPact Tiers
Rather than having a one-size-fits-all product, Holcim delivers ECOPact in a three-tiered system:
- ECOPact (30–50% reduction in carbon emissions)
- ECOPact Prime (50–70% reduction)
- ECOPACT Max (70–90% reduction)
Each tier can be enhanced with the addition of recycled concrete aggregates ECOPact+ range, according to the company. Kevin Peart, Senior Vice President and General Manager of the Mountain Region, Holcim, believes that Holcim has become “one of the first movers in the concrete industry.”
For the Populus hotel, this sustainable concrete was integral to the design process. The project’s utilization of ECOPact accounts for 65% of the total cubic yards of concrete poured, with an anticipated reduction of 765 tons in the concrete's embodied carbon compared to traditional concrete.
A similar story is told at 55 H Street, a Georgetown University residence hall (above). The project team had a specific challenge: they needed a concrete blend capable of attaining a 28-day design strength of 5,000 psi, while also achieving a high-early strength of 3,000 psi within a span of two to three days. ECOPact delivered, and 55 H Street became “one of the most sustainable buildings in D.C.,” says Zachary Lovett, Project Pursuit Manager, Holcim.
As the built environment continues to find ways to reduce its impact on the planet, innovative materials like ECOPact may help drive the change that architects, engineers, and contractors desire.
Related Stories
Sponsored | Flooring | May 18, 2015
Suburban L.A. high school battles moisture-soaked flooring
School officials had to take action when popped flooring created trip hazards
Multifamily Housing | Mar 16, 2015
New Jersey Supreme Court puts control of affordable housing agency in the courts
The court said the state’s affordable housing agency had failed to do its job, and effectively transferred the agency's regulatory authority to lower courts.
| Nov 7, 2014
Prefab helps Valparaiso student residence project meet an ambitious deadline
Few colleges or universities have embraced prefabrication more wholeheartedly than Valparaiso (Ind.) University. The Lutheran-based institution completed a $27 million residence hall this past summer in which the structural elements were all precast.
| Sep 30, 2014
Breakthrough concrete mix could reduce carbon emissions by 60%
Scientists at MIT have found a way to decrease the carbon emissions that result from concrete production: reducing the ratio of calcium to the silicate-rich clay.
| Aug 5, 2014
New bomb-proof concrete mixture used in One World Trade Center
The new concrete mix deforms instead of breaking, removing the threat of flying debris in an explosive attack.
| Jul 11, 2014
Are these LEGO-like blocks the future of construction?
Kite Bricks proposes a more efficient way of building with its newly developed Smart Bricks system.
| Jun 12, 2014
Austrian university develops 'inflatable' concrete dome method
Constructing a concrete dome is a costly process, but this may change soon. A team from the Vienna University of Technology has developed a method that allows concrete domes to form with the use of air and steel cables instead of expensive, timber supporting structures.
| May 15, 2014
'Virtually indestructible': Utah architect applies thin-shell dome concept for safer schools
At $94 a square foot and "virtually indestructible," some school districts in Utah are opting to build concrete dome schools in lieu of traditional structures.
