Landscape and Irrigation is read by decision makers throughout the landscape and irrigation markets — including contractors, landscape architects, professional grounds managers, and irrigation and water mgmt companies and reaches the entire spetrum.
Issue link: https://read.dmtmag.com/i/776403
www.landscapeirrigation.com Landscape and Irrigation January/February 2017 19 GREEN ROOFS from penetrating the waterproofi ng system; and a drainage board, which temporarily retains water, allowing it to drain away at a slower rate. This layer also provides root ventilation for plants installed in the green roof. Next, fi lter fabric was used to help the drainage layer function effi ciently by preventing fi ne particles from being washed out of the substrate through irrigation. All of this was covered with 200 cubic yards of engineered growing medium, which included the HydRocks mix designed to be lightweight and support vegetation, while accommodating the project's specifi cations. The growing medium was installed in a four-inch layer, using a pneumatic blower truck. McGaughy specifi ed the lightweight engineered soil for the green roof installation because of the engineered soil's permeable properties, but also the lighter-weight option lowered costs for transporting the material to the site than traditional soils. "Weights or dead loads are always an issue," said McGaughy. "By using the lightweight aggregate soil, shipping, installation, exact drainage rate, and weight can be predetermined." The weight caused by soil on green roofs, especially when compacted with water, is as much a concern for the related efforts involved in the design-build process as for the weight-bearing capacity of the building, plant selection and the structure itself. Greening up the green roof Once the engineered growing medium was in place, Greenrise Technologies then planted 14 varieties of sedum for the fi nishing touch. In the end, it is often the vegetation that gets the attention, but much goes into developing a successful growing environment that will provide plants with the nutrients they need to survive and thrive. The sedum beds benefi t biologically from the engineered soil's components as well. Multiple sedum varieties were chosen with dense, mounding habits and caulifl ower-like fl ower heads. They were selected for their ability to peak even in Atlanta's hot and humid summer climate and for their capability to mature to large fl at heads or sprout with lobed foliage and small fl owers. The planting beds also were designed to include base turf and fountain grass to feature densely clumped growth as a focal point. Art installations, meandering pathways and bench seating added to the space's ambience and practicality adjacent to top restaurants and trendy retail. "The result is a green roof that has livability, ornamental horticultural and storm water benefi ts, while providing the structural reliability to support the building's architecture," said Speck. "It reduces the urban heat quotient signifi cantly and provides an aesthetic quality that improves the live, work and play experience for those who frequent Ponce City Market." Don Eberly is the president/CEO of Eberly & Collard Public Relations, a national marketing fi rm specializing in the architecture, design, engineering, construction, and building product industries (www.eberlycollardpr.com).