2021 Owens Corning Sustainability Report | Our Approach | Stakeholder Engagement & Material Issues | 36 MATERIALITY & ENGAGEMENT INITIATIVES In 2021, we conducted another refresh of the 2019 Materiality Assessment, in which we sought to confirm the continued relevance of the existing Material Topics and their relative positioning within the materiality matrix visuals, for the company as a whole and broken out by region. The refresh and review process can be described in three steps: ■ Reassess scopes of material topics and input data for material topics. ■ Refresh the AI-driven aspects of the assessment to incorporate new industry benchmark, regulatory, news, and social data into the models. ■ A sustainability review to determine if the materiality assessment conducted in 2019 continues to accurately represent the company’s sustainability strategy, impacts, and goals, or if there has been a significant enough change to the company strategy or model inputs to require further revisions. In 2021, Owens Corning acquired vliepa GmbH, a German- based company specializing in the coating, printing, and finishing of nonwovens, paper, and film for the building materials industry. With this acquisition came an opportunity to reexamine our approach to sustainability materiality. We developed a process for assessing the materiality impact of new acquisitions, which looks at aspects such as the acquisition’s size and location, the products that they make, the markets they serve, their environmental footprint, and their social impacts such as safety and inclusion and diversity. This process enables us to determine if the acquisition is significantly impactful in scope or scale compared to our company, which can then lead to updates to our sustainability priorities and impacts that reflect both our existing company and the acquisition. Based on this review, it was determined that the vliepa acquisition did not require an update of our materiality assessment topic scopes, or relative matrix positions. This was due to vliepa’s alignment within Owens Corning’s existing product mix, as well as vliepa’s small size relative to Owens Corning as an enterprise. While this acquisition did not require an update to our sustainability materiality, it was an important step to develop a process for the consistent consideration of new acquisitions, as this process can potentially be used in the future as well. A sustainability review was conducted of the topic mapping, and the preliminary matrix data, taking into account the changes due to refreshing the data sources, and in the case of new Datamaran ontology, refreshing the underlying aspects of the material topics themselves. Through this assessment, it was determined that some topics did have slight movements in their weighting due to the new data. Despite these minor movements, the fundamental positions of the Material Topics, such as where topics lie in regions of the graph, were not significantly changed, and the Material Topics and their visual representations continue to represent Owens Corning’s material sustainability topics accurately. Photo submitted by: Leila Pourzahedi | Granville, Ohio, U.S. Squamish, British Columbia, Canada.