In 2008, Allstate Insurance Company began building a new, state-of-the-art green data center in Northwest Illinois. Due to the plans for the site and the need to store all storm water in on-site retention ponds, retaining walls were needed. These walls were to be constructed around the ponds to allow for adequate capacity in the ponds without exceeding an acceptable footprint. Typically, retention ponds are not known for their architecturally pleasing features. For this project however, Allstate and landscape designer Robert Mueller wanted to do something different. Mueller is the owner of Landscape Artist, a company that specializes in natural and native landscape planning, design and installation. He decided to use the ponds and their requisite walls as a feature of the site, rather than an aesthetic liability.
To achieve this end, he required a wall material that would meet specific criteria. Sustainability drove all aspects of design and construction for the building and the site. And since the data center was designed to meet Leadership in Energy and Environmental Design (LEED) Gold certification standards, it was critical that the retaining wall materials contributed to the site’s certification. Second, the overall cost had to be within budget. Third, the wall material had to allow for structural engineering. Fourth, the wall had to be easy to install. And finally, the wall had to visually blend in with the natural surroundings.
Mueller originally spotted the Rosetta Wall system at a regional industry event (Mid-America Horticultural Trade Show) and knew that it would work well for the Allstate project.
“The product is unique and the engineering capabilities are very good,” Mueller said. “Naturally, the aesthetic look played a role in choosing the product—we were going for an outcropping look because the overall site concept was a natural setting. The plantings we specified there were all native from trees, shrubs and grasses to expansive wildflower areas. It just seemed like the right choice to use the Rosetta in the ponds to give it the natural, outcropping look yet meet budget constraints. Rosetta staff provided responsive accurate technical and engineering support.”
Rosetta is a structural wall system that is created by casting architectural wetcast concrete into moulds taken from actual weathered limestone. The product has been designed to allow the units to interlock, giving it the structural benefits of large concrete retaining wall units, while maintaining the aesthetic benefits of natural stone.
“The installer was happy with how things went,” Mueller said. “You’re also saving a lot of time because with blocks the size of Rosetta units you’re setting fewer blocks to accomplish the same square feet of face by comparison to many smaller pre-cast wall blocks.”
Steve Link, P.E. of Service Konstruction Supply was impressed with the project, saying, “The Rosetta product not only offered the aesthetics of natural stone that Allstate and Mr. Mueller were looking to achieve, but also provided a more economical option and the ability to be engineered.”
On the sustainability front, Rosetta contributed to the overall goals of the project. One of the LEED criteria gives points to projects that use regional materials. The standard gives credit if a certain percentage of the products used are manufactured within 500 miles of the project location using raw materials that are extracted within 500 miles of the location. The Rosetta wall product exceeded the standard for regional materials. Another LEED criterion gives points to projects that use products with recycled content. The Rosetta units used on the Allstate project used 25% less carbon-intensive Portland cement than is typical by replacing cement with recycled fly ash. This substitution was an important contribution to the LEED criteria for recycled content for the project as a whole.
By using the Rosetta Wall System on the Allstate Data Center project, Mueller was able to create a beautiful landscape feature out of the structural walls needed for the retention ponds, all the while contributing to Allstate’s sustainability goals. For more information about how Rosetta can provide the perfect solution for your project, please visit www.discoverrosetta.com. A video tour of the new data center is available at www.youtube.com/allstate.