RoofViews

Building Science

Building Science FAQ — Ep. 4

By Don Kilcoyne

January 04, 2019

episode 4 of building science FAQs

Air Barrier vs. Vapor Retarder

Welcome to Episode 4 of The Building Science FAQ series.

The Building Science FAQ video series explores some of the technical questions that crop up when specifying a low-slope roof.

In this episode, Jennifer Keegan, director of building and roof science, GAF, and Jim Kirby, GAF building and roofing science architect, address a common area of confusion: "What is the difference between an air barrier and a vapor retarder?" While an air barrier stops air leakage, a vapor retarder reduces moisture diffusion to reduce the risk of condensation forming in the roof assembly. But can an air barrier be a vapor retarder?

Watch

About the Author

Don Kilcoyne, a writer and editor for GAF, crafts marketing campaigns and language that communicate the company brand, initiatives, products, and priorities in video, print, and social media, as well as GAF Roof Views. He joined the GAF team in late 2016, bringing a background as a creative director and author.

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