Maryland Green Building Network
December 4, 2001 – 6:30–8:30 pm
EPA Building – Annapolis, MD
Alan Abrams, Heritage Bldg & Renov.
Deborah Bock, Mont. Co. Permitting
Rick Brush, Mont. Co.
Seekey Cacciatore, Mont. Co.
D.J. Campbell, Citizen
Sara Colhoun, Citizen
Stan Edwards, Citizen
Ginger Ellis, AA Co. P & Z
Diane Evans, MD-DNR
Maureen Fine, Bowie Sierra Club
Stephen Gilliss, MD-DGS
Dale Grant, Bowie Sierra Club
James Kantor, Parallax, Inc.
Mike Li, DNR
Tom Lofft, Liberty Village Cohousing
Tatiana Lutz, Builder
Sean McGuire, GBN Coordinator
Jonathan Meyer, Meyer & Sons
Albert Nunez, Cap Sun
Nadine Piontka, Mont. Co. Permitting
Dominic Quatrocchi, Mont. Co.
Pamela Rowe, City of Rockville
John Scabis, City of Rockville
Rob Shank, Interface
Amar Sikand, Yorktown Condo Assoc.
Joan Simons, SKS, Inc.
Shanna Sizemore, City of Rockville
Jeanette Stewart, EcoStewards Alliance
Louisa Thompson, Native Plant Society
Karin Victorio, NAHB Research Center
John Vlah, Holophane Lighting
Rick Wharton, Mont. Co. Permitting
Cameron Wiegand, Mont. Co. DEP
Hank Zacharias, HydroTech
Laura Zeiher, Environ. Design & Consult.
Introductions and Review of Upcoming Events: Sean asked that attendees introduce themselves and then reviewed upcoming events as stated in the GBN meeting announcement.
Rob is an Account Executive with Interface, a cutting-edge, carpet company specializing in innovative, more sustainable techniques. Rob shared several samples and explained approaches that will reduce overall production and consumption of materials. Interface is a proven leader in identifying innovative, sustainable approaches, and Rob showed attendees several of the different techniques Interface employs. Also, Interface recently released their new website highlighting their commitment to sustainable products. Please check it out at www.interface.com.
Matt began his discussion of green roofs by sharing why he became interested in the industry. His love for nature drove him to more innovative technologies and to incorporate more natural components into existing construction. That took him to explore more European techniques, where roofs are looked at as an opportunity. Here in the US, roofs are an afterthought. If you look at our roofs, they are huge, expansive, and unsightly. When we look globally, the US if far behind in utilizing green building techniques. For instance, in Germany 50% of every building roof must be living.
The biggest challenge is to convince architects that a green roof will not leek. Living roofs can be made watertight, and they have a proven track record over a long history. Frank Lloyd Wright even had living roofs in his designs. Matt reviewed the characteristics that HydroTech’s membranes enjoy. They last longer – traditional decks need replacing after about 15 years, where HyrdroTech’s roofs last for decades. Contractors also like the membranes because they have few callbacks, are easy to apply, and contain little toxic fumes. However, contractors must be certified. Matt reviewed several national examples of their roof membranes.
Matt then discussed traditional living roofs. Most living roofs are only 6”-7” thick with a lightweight sod, and grass that grows about 6”-7” high. This structure weighs about 1-2 lb/sq/ft. The consequence of these roofs is that they are 30% more energy efficient as they cool the interior. To enjoy winter savings, a 2-foot heat barrier must be constructed. But the often under-appreciated aspect of a living roof is the tremendous aesthetic satisfaction enjoyed by employees and visitors.
Another environmental issue that living roofs address is the Urban Heat Island Effect. This occurs when solar heat is trapped in urban centers and ambient temperatures increase. Every 1-degree increase in an urban environment results in a 3% increase in energy costs. The increased heat also has a direct effect on micro-climates. Living roofs can be a cost effective manner to abate these environmental hazards. They also provide carbon sinks, stormwater management, and increased oxygen sources.
Matt then more carefully reviewed the variety of plant material and required construction for a living roof. The larger the project, and the more soil is required and, subsequently, the greater the weight and structural requirements. Some roofs can weigh up to 150 lbs/sq/ft. Yet, this increased natural matter performs wonderfully to abate stormwater run-off. Matt also explained the details of the HydroTech layering system. Their “egg cartons” collects rain, allows excess run-off, and still allows for evapotranspiration.
Lastly, Matt reviewed the applicability of living roofs for residential buildings. There are many applications for living roofs, specifically to reduce cooling costs. While most companies specialize in commercial buildings, most contractors and architects can design green roofs onto structures. The maximum pitch of a roof is 17% for plant material. Matt did explain that green roofs are exceptional options for strawbale houses.
For more information, please check out their website at http://www.hydrotechusa.com/start.htm.