One of world's most advanced sustainable construction studies is reviewing an interesting application of concrete construction. Students at the British Columbia Institute of Technology's Centre for Advancement of Green Roof Technology are measuring the performance of various materials for green roof structures, including insulating concrete forms (ICFs).
During the next two years, students will measure key performance qualities of several 6x6-foot test structures called Roofing Evaluation Modules (REMs). First, they will track the amount and quality of stormwater runoff from the roofs. Then they will record thermal performance. Most of the REMs are wood frame structures, but one is made with insulated concrete panels.
Quad-Lock, an ICF manufacturer based in Surrey, British Columbia, has supplied wall and roof ICFs for the project. Its Quad-Deck product, a pan-form for suspended concrete floors, is well-suited as a green roof substrate. The system forms one-way, T-beam suspended spans that hold live loads of more than 100 pounds per square foot. Two integral steel beams molded into the product from end to end support and reinforce its expanded polystyrene panels.
The T-beam configuration can reduce a structure's steel consumption by 50% and its weight by 40%. It also reduces shoring requirements by 50% compared to hand-set suspended forms. On the flip side, the panels are insulated with R-values up to R34, and owner ready for drywall or a suspended ceiling to be installed.
The concrete decking also addresses a major concern with green roofs: leakage. Concrete resists damage from wet soil and insects, and with the help of crystalline admixtures, provides a waterproof surface.
While the study's results could increase market share for ICF roofs, ICF customers could benefit most. “We know there is a 40% to 70% increase in thermal performance for concrete versus wood construction,” says Douglas Bennion, Quad-Lock's senior training consultant. “We may be able to add a 25% improvement in the thermal performance of a concrete roof and extend the life of the roofing materials. If we can demonstrate reduced water runoff with an engineering study, a commercial building's permit impact fees could drop thousands of dollars, offsetting the cost of installation.”
Keith Miles, owner of Northern Hills Redevelopment in Orange, N.J., has seen another type of savings. His Alpha Lofts feature green roofs for the environmental benefits, as well as much-needed green space on the commuter line to New York City. “Using insulated Quad-Deck panels allowed us to find efficiencies, and sharpen our pencils to come up with a better bottom line,” says Miles.
Ken Branyan, owner of Ken's Konstruction in National Park, N.J., recently completed the Wat Mongkoltepmunee Buddhist Temple in Bensalem, Pa., where a Quad-Deck green roof covers the 4000-square-foot terrace. “It allowed us to put the job together quickly and still give the customer a good quality product,” says Branyan. He also plans to put a Quad-Deck green roof on his house, creating more usable space and a showcase for customers.
Quad-Lock will use the study to educate architects and designers on the sustainable aspects of ICFs, including green roofs. They also want to educate producers to become green roof experts.
“ICFs are the perfect entry into green construction for ready mix producers," says Bennion. "Our dealers can provide the tools they need to create a green roof, from start to finish.” This includes consulting with Quad-Lock on building designs, and working with their suppliers, such as agronomists who design special growing medium (dirt) for each green roof's environment.
See how Quad-Lock products were used in these green roof projects:
Northern Hills Redevelopment, Orange, NJ
Wat Mongkoltepmunee Buddhist Temple Ken's Konstruction, National Park, NJ