Issue link: http://digital.canadawide.com/i/147234
Aloft Vaughan Mills Hotel, Vaughan, Ontario. Durex Quantum Select EIFS System features a 10-mm drainage cavity. Applicator: Limosano Plastering & Stucco Inc. Photos courtesy Durabond Products Ltd. wall designs should employ a perfect barrier-drained system i.e., they should use a drained two-stage joint between the concrete barrier elements at all penetrations." There's more good news. According to Robert Burak, president of the Canadian Precast/Prestressed Concrete Institute (CPCI), architectural precast walls using a drained, two-stage joint system between the concrete barrier elements do not require additional rainscreen. 14/ august 2013 p12-21Envelope.indd 14 Although the almost-endless residential realty boom in Toronto and Vancouver has been winding down of late, demand for quality in this sector has come from places that are perhaps not on the radar of some Canadian-based suppliers. "Demand is pent up in major northeast U.S. cities," says Andrew Rogers, president of Sound Solutions. "The Boston and New York areas are seeing a big upswing in multiresidential. Both cities are requiring quality cladding in some districts." Solar shading is also seeing increased demand, he says, adding that his firm recently filled its fourth large order for solar shading products from Levolux. As the focus on energy consumption sharpens, with increased demand for greater energy-efficiency and tougher standards like those in the new National Building Code of Canada, debate could intensify around some envelope issues. Certainly, there is some questioning of the emphasis on R-values. A paper by David B. South, president of Texasbased Monolithic Constructors Inc., entitled "R" Fairy Tale: The Myth of Insulation Values argues that the process to determine the R-value of a product involves an ASTM test that is based on a flawed design. It favours fibre insulation materials like fibreglass, rock wool and cellulose fibre. Considerations of solid insulation provided little input into the ASTM test design. "The test does not account for air movement (wind) or any amount of moisture (water vapour). In other words, the test used to create the R-value is in non-real-world conditions. For instance, fibreglass is generally assigned an R-value of approximately 3.5," the paper states. It adds that it can only achieve that R-value if there is no wind or moisture, which is "unrealistic." "The R value is based on lab conditions," adds Keith Bowie, board director for Manitoba with the Canadian Urethane Foam Contractors Association (CUFCA) and VP of EcoLogic Building Envelope 13-07-12 2:19 PM