Whole Building Sensitivity Analysis for Thermal Bridging

Please note: The attached file below contains a paper and a presentation in pdf format from the BEST5 conference. Open with Adobe Acrobat for best results.

As demand increases for building enclosures that have greater detail complexity and higher performance requirements, so too does the need for procedures to evaluate the impact of thermal bridging on the performance of the enclosures. This paper outlines a procedure for using available catalogue values for linear and point transmittance of various common enclosure details to conduct a sensitivity analysis to estimate the relative impact of different detail conditions on the overall effective u-value of an enclosure design. This procedure allows selection of details for 2D or 3D modelling based on overall impact, and allows designers to make informed decisions regarding additional efficiency measures. This procedure was initially developed for several high-rise luxury apartments in New York City, allowing for thermal bridging to be accounted for in the building energy model, and also allowing the owners to select additional efficiency measures based on the value and impact on the thermal enclosure of the whole building. The presentation reviews results and lessons learned from implementation of the procedure, and provide a basis for future practice on design projects.