
Session X - Room
December 9, 2025 - Time
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Theory and Practice for Attics and Cathedral Roof Slopes in Cold Climates
Henri Fennell, Consultant, HC Fennell Consulting, LLC, North Thetford, VT
About this program:
This session will describe the procedures for diagnosing and correcting insulation, radiant warming, and air leakage problems in attics and cathedral roof slopes, including near-flat roofs. An overview of the related ventilation issues is included. Pros and cons of vented and unvented designs are covered as methods for preventing problems in new construction, or as a method of remediating problems by changing from one strategy to the other.
Learning objectives:
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Participants will be able to choose when to use vented and unvented attics and cathedral roofs in their designs.
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Participants will be able to diagnose insulation and air leakage problems in attics and cathedral roof slopes.
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Participants will be able to employ tracking of the attic and roof temperatures and pattern analysis during the work to prioritize leakage sites and reduce remediation costs.
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Participants will be able to verify performance improvements using the same diagnostic tools that they use for other building performance diagnostics.
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Participants will learn the various diagnostic methods and how to prioritize remediation work to maximize return on investment.
Who Should Attend:
Builders, architects, energy auditors, insulation contractors, HVAC professionals, weatherization specialists, building inspectors, and anyone involved in diagnosing or designing building envelopes in cold climates.
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About the Presenter:
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Henri Fennell is a building envelope specialist and architect with forty-five years of experience in energy conservation design, manufactured products, and services. His work with polyurethane foam began during the energy crisis of the 1970s.
His experience has included practicing architect and building envelope remediation and commissioning consultant. Major historic projects include the Guggenheim Museum. He has designed several new micro-load buildings, including a cutting-edge net-zero energy research structure in Antarctica.
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For the last ten years he has developed and implemented remediation plans and standards for misapplied foam projects.
He has four energy-related U.S. patents, and has contributed to ASTM standards, ASHRAE Journal, and is often cited in articles related to energy conservation and building performance.
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Program Level:
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Basic
Intermediate
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Content Area(s):
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All buildings
Balancing Energy Efficiency & Indoor Air Quality
Ventilation
Construction Practices
Building Science
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