Selecting and installing the green roof system
TKWA specified the LiveRoof Hybrid Green Roof System from LiveRoof, LLC, Spring Lake, Michigan. The design of the system’s modules establishes a green roof as a dense, seamless planted surface rooted in a continuous, interconnected layer of soil. This creates a cohesive and sustainable ecosystem across the rooftop that functions naturally and thereby maximizes roof membrane protection, building energy savings, rooftop aesthetics, long-term plant health and environmental benefits.
This system is compatible with different types of flat roof systems and single-ply roof membranes. On the Meeting House roof, the roofing contractor Langer Roofing & Sheet Metal, Milwaukee, Wisconsin, installed the LiveRoof over a 60-mil fully adhered TPO membrane and a 4-mil EPDM slip sheet manufactured by Carlisle SynTec Systems.
When LiveRoof modules are delivered to a job-site, they arrive abundantly pre-vegetated with regionally adapted, locally cultivated plants that are full-grown, thriving and ready for the rigors of the rooftop. This means that contractors and building owners do not have to wait two or three years to determine whether the plants will survive, grow to maturity and fill in to establish a fully green roof.
After the LiveRoof installation was complete, the Langer Roofing & Sheet Metal crew left behind an established green roof that looked like it had already been growing for several years, which provided the roofing contractor greater assurance of the project’s immediate success and long-term, trouble-free maintenance.
The sweeping radius of the roofline was a challenge. Installers had to cut modules to establish and express the curve. With a well-established root system holding the soil and plants in place, LiveRoof modules were cut to size and shape without the soil and plants falling out. This proved to be an important advantage on this job.
Benefits and surprises
The stormwater management features, topped off by the green roof, have proven to be effective. Even during 5-inch rainstorms, there is no runoff on to the neighboring property. On an 85-degree day, the copper roof heats up to 115 degrees, but the green roof remains at 85 degrees. This translates into decreased energy use and costs.
Ten varieties of Sedum are featured in the Meeting House’s green roof so it flourishes like a meadow changing colors with the seasons. The stunning view of the green roof from the nearby University of Wisconsin Children’s Hospital was a surprise. The fact that the beauty of the Meeting House green roof can be enjoyed and appreciated by patients, families and caregivers at the hospital came as an unexpected, but welcomed, bonus benefit.