b'Energy LossesTowards Codification ofEnergy Losses from Fasteners on Commercial Roofing Assemblies By Sudhakar Molleti, PhD, PEng and Bas Baskaran, PhD, PEngIntroduction that is uncompressed and continuous across all structuralthough these studies do not provide general encompassing Building energy codes and standards, such as ASHRAEmemberswithoutthermalbridges,otherthanfastenersmethods that may be applied to reach the building code 90.1,EnergyStandardforBuildingsExceptLow-RiseResi- and service openings. 1This definition acknowledges thedesign thermal values, they have certainly highlighted the dential Buildings,theInternationalEnergyConservationimportance of thermal bridging but undermines the ther- potential significance of the thermal bridging of fasteners Code (IECC) and the National Energy Code of Canadamal bridging from resulting fasteners (Figure 1) or protru- in commercial roofs.sions through the assembly, such as pipes, ducts and roof- Inlow-slopemembraneroofingsystems,mechanical for Buildings (NECB) provide minimum requirements fortop equipment. There exist some simulation studies onfasteners are used to secure the individual components the design of energy-efficient roofs. They also present ap- thermal bridging (Burch, Shoback, & Cavanaugh, 1987; 2 and provide resistance against wind uplift forces. Current-proaches to determine the thermal transmittance (U value)Atchley, Desjarlais, & Christian, 2000; 3Olson, Saldanha,ly in the roofing industry, documents such as ANSI/SPRI-of the roof assembly, which are limited to roof assemblies& Hsu, 2015; 4Gulati, Suddapalli, & Srinivasan, 2016; 5andWD1 7and FM Approvals 8provide performance-based fas-withcontinuousinsulation.Thedefinitionofcontinu- Singh, Gulati, Srinivasan, & Bhandari, 2016 6 ) that havetener densities for mechanically attached roofing systems ous insulation, according to ASHRAE 90.1, is insulationestimated the thermal penalty of fasteners in roofs. Al- (MARS) and partially adhered roofing systems (PARS) for 20ONTARIO ROOFING NEWSISSUE 1 2020 THE ONLY SOURCE FOR PROFESSIONAL ICI ROOFING CONTRACTORS IN ONTARIO ORN'