Owens Corning

Management of the Company is responsible for establishing and maintaining adequate internal control over financial reporting as such term is defined in Rules 13a-15(f) and 15d-15(f) under the Securities Exchange Act of 1934.

Management has assessed the effectiveness of the Company’s internal control over financial reporting as of December 31, 2024 based on criteria established in the Internal Control-Integrated Framework in 2013 issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

On May 15, 2024, the Company completed its acquisition of Masonite International Corporation ("Masonite"). As a result, the Company's management excluded the operations of Masonite from its assessment of internal control over financial reporting as of December 31, 2024. Masonite represented 11% of the Company's consolidated total assets as of December 31, 2024, and 13% of the Company's consolidated Net sales for the year ended December 31, 2024. SEC guidelines permit companies to omit an acquired entity's internal control over financial reporting from its management assessment during the first year of the acquisition. We plan to fully integrate Masonite into our internal control over financial reporting in 2025.

PricewaterhouseCoopers LLP has audited the effectiveness of the internal controls over financial reporting as of December 31, 2024, as stated in their Report of Independent Registered Public Accounting Firm within Item 8. Financial Statements and Supplementary Data.

Based on our assessment, management determined that, as of December 31, 2024, the Company’s internal control over financial reporting was effective.