Sponsored by GAF | Siplast | Presented by Andrea Wagner Watts and Benjamin Meyer
Live Webinar Airing on May 13, 2025 at 02:00 PM ET
It is a common question: “Do I need a vapor retarder on this roof?” The frustrating answer is often “it depends.” This presentation will uncover the differences between air barriers and vapor retarders and the benefits of each to improving the durability and efficiency of your building enclosure. Additionally, it will discuss critical installation details as it relates to the roof and roof/wall interface. Case studies will be presented to show real-world design and installation considerations and challenges. What’s new, what’s the same, and what to think about when you design roof assemblies in different climate zones and over different types of occupancies with varying construction types.
Photo courtesy of GAF
![]() |
Andrea Wagner Watts is the Building Science Education Manager for GAF | Siplast Building & Roofing Science, engaging with industry professionals to provide guidance, technical support and education for roof and wall assemblies. With more than 15 years of experience in the industry, Andrea strives to improve the overall performance of the building enclosures through application innovation, product development and building science research. Andrea has published on building science, assembly interfaces, durability and resilience and holds multiple patents. She serves as an executive board member of ABAA, is the co-chair of their Technical Committee and chairs the ASTM E06 and D08 Task Groups on air barriers assemblies. |
![]() |
Benjamin Meyer is the Building Enclosure Business Director with Siplast. Previous experience includes: enclosure consultant principal, technical management for enclosure products, architecture, real-estate development and construction management. Serves as a past Member of the LEED Technical Committee, Chair of the ASHRAE 90.1 Envelope Committee, and a Director of ABAA. |
The Building and Roofing Science team offers regional expert building enclosure collaboration through design, specification, and educational support for customers of GAF and Siplast, both Standard Industries companies. GAF is North America’s largest roofing manufacturer with more homes and businesses in the U.S. protected by a GAF roof than any other product. Siplast, a leader in building enclosure systems, offers a portfolio of advanced, high-performance SBS-modified bitumen, PMMA liquid-applied, PVC KEE, lightweight insulating concrete, wall air & water barrier systems, and amenity/vegetated systems.
Originally published in Building Enclosure
Originally published in March 2025