Moisture Vapor Transmission

Water, Water Everywhere and Not a Drop to Drink: Practical Building Science to Keep Walls Dry

Newer homes, materials and code requirements have changed the way “invisible” water (water vapor) must be managed to avoid it becoming visible in unwanted ways. Water vapor control is one of the trickiest and riskiest areas of building and energy code compliance. The old “rules of thumb” are no longer reliable or universal. This session, presented at IBS 2017, provides actionable prescriptive guidelines for integrated insulation and vapor control strategies. Specific applications and unique situations from the audience will also be explored.

Assessment of Water Vapor Control Methods for Modern Insulated Light-Frame Wall Assemblies

A comprehensive assessment of the state-of-the-art of water vapor control for modern, code-compliant, light-frame wall assemblies. The primary goal of this effort is to evaluate and reconcile existing building science knowledge and practices. An important secondary goal is to support the development of practical and comprehensive water vapor control requirements or recommendations that may be used as a basis to reach various audiences and serve multiple purposes, including building industry education and building code development.