X0407 4 2023-06-06 0 0001370946 Owens Corning OC 0001748562 Smith Gunner ONE OWENS CORNING PARKWAY TOLEDO OH 43659 0 1 0 0 President, Roofing 0 $.01 Par Value Common 2023-06-06 4 S 0 6900 115.01 D 31153 D This reported transaction was made pursuant to a Rule 10b5-1 trading plan entered into by the reporting person prior to February 27, 2023. The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $115.00 to $115.07, inclusive. The Reporting Person undertakes to provide to Owens Corning, any security holder of Owens Corning, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. The total amount of holdings reflects an acquisition on May 31, 2023 of 238 shares through the Issuer's Employee Stock Purchase Plan, which is exempt under Rule 16b-3(c). Katherine M. Serevitch, Attorney-in-Fact 2023-06-07