AIA Austin BEC: Hidden Underperformers – True Impacts of Thermal Bridging

Session Overview:
The effective thermal resistance of building enclosure assemblies is essential information when evaluating the overall thermal performance – for more accurate energy modeling and a better understanding of how and where money should be spent to provide a better building design. As energy codes continue to request better performance and lower energy use, knowledge of how a building enclosure actually manages heat flow becomes critical.

The recently published (and freely available) BCHydro Building Envelope Thermal Bridging Guide was prepared by Morrison Hershfield based upon the ground-breaking research work undertaken for ASHRAE project 1365-RP.

This Guide promotes energy-efficiency in buildings by providing a straightforward method for assessing building enclosure design and quickly determining where the problem details exist.

• What is the impact of using thermally broken clip systems versus regular z-girts?
• Do window details really matter?
• Should I care about adding more insulation?

With its local and international significance, the Guide has already become a reference source used by local jurisdictions, regulatory bodies and utilities in determining real thermal performance.

This presentation looks at thermal bridging effectiveness, how you can gain an understanding of the research and how you can take advantage of this information to improve your enclosure designs.

Learning Objectives:

• Understand the disconnect between actual building envelope performance versus theoretical assumed performance
• Quantify the impact of thermal bridging in the context of effective R-values and whole building energy performance
• Show how thermal bridging can be mitigated and compare to other energy efficient measures

David Kayll, Principal and Building Science Specialist, will be presenting True Impacts of Thermal Bridging at the AIA Austin Building Envelope Council’s (BEC) April monthly meeting.