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Technical Guidance - Thermal bypass risks

Category: Guidance

Policy-makers, developers, designers and constructors need to be confident the buildings they are responsible for will perform as predicted. The evidence base considered in this paper clearly demonstrates that failures in design and construction do not have to be the norm and that they can, with the right knowledge, intent and skill, be addressed in practice and on the building site. As has been demonstrated in the literature, Passivhaus buildings clearly demonstrate how performance gaps can be closed reliably (Johnston et al., 2020).

This literature review, and the supplementary analysis undertaken to create a contextualised understanding of thermal bypass, supports the construction of contemporary high performance, low energy and Passivhaus buildings and clearly demonstrates that, if thermal performance gaps are to remain within an acceptable tolerance, then continuous insulation should be encapsulated on all sides by uninterrupted, unbroken air and wind barriers. Only once this is achieved will buildings deliver the energy savings, carbon emissions, comfort, health and well-being that owners, investors, occupants and future generations rightly expect. 




Thermal bypass risks | Passivhaus Trust | September 2022

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 Published: September 2022


This paper has been recognised by many professional bodies. 

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