Reference: Breathability: The Key to Building Performance (2005) May, N.

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Abstract or summary

This paper examines first the various types and mechanisms of breathability, and how different materials perform in different ways. It examines materials in particular common situations and the consequences of breathability for the main areas affected by water: water on the outside of buildings (rainwater penetration), water in the structure (thermal performance and interstitial conditions), surface condensation and indoor air quality. It considers four basic principles for the successful design and construction of breathable buildings: compatibility between elements, making the fabric do the work, building in safety margins, and whole house design. Finally it draws some conclusions about the science of breathability and the future of construction.