On January 18, 2022, John L. Buckley, President, Siding Business Unit of Cornerstone Building Brands, Inc. (the Company"), informed the Company of his intention to leave the organization. Mr. Buckley intends to remain in his current role through at least the end of the first quarter of 2022 (the Transition Date") to help with a smooth transition. Mr. Buckley's announced intention is not the result of any disagreement with the Company with respect to any matter relating to the Company's operations, policies or practices.