X0306 4 2023-02-06 0 0001370946 Owens Corning OC 0001339551 Chambers Brian ONE OWENS CORNING PARKWAY TOLEDO OH 43659 1 1 0 0 Chair, President and CEO $.01 Par Value Common 2023-02-06 4 F 0 5684 99.61 D 255293 D $.01 Par Value Common 2023-02-07 4 F 0 1664 99.83 D 253629 D $.01 Par Value Common 25 I By adult son Shares withheld upon vesting of restricted stock units to satisfy tax withholding obligations. Reflects shares withheld from restricted stock unit award to satisfy FICA and related income tax obligations arising from the reporting person being eligible for retirement vesting under the terms of the Owens Corning 2019 Stock Plan. The reporting person may be deemed to have acquired beneficial ownership of these shares upon his adult child moving into his household. The reporting person disclaims beneficial ownership of these securities, and this report shall not be deemed an admission that the reporting person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. /s/ Jeffrey S. Wilke, Attorney-in-Fact 2023-02-08