This course is intended to give an overview of an aspect of Sustainable Design (SD): Air Barriers. Air barriers meet this criterion because they support the definition of sustainable design through energy efficiency, building longevity, and improvement in air quality. This presentation meets the Health, Safety, Welfare (HSW) guidelines specifically around Health and Safety. It focuses on the HSW topic of Weatherproofing and Insulation. Greater than 75% of this course will focus on these topics. This course will provide an overview of air barrier construction in commercial buildings and offer insights into the benefits of air barriers. Design considerations will be presented both around specification and installation. The importance of substrate preparation is shown in order to achieve desired air barrier performance. Different materials and application methods are covered, including benefits and considerations. Application errors are shown for field verification and correction before building completion. Finally, test methods to verify air barrier performance are shown. Typical warrantees are described to ensure air barrier effectiveness.