X0609 4 2026-04-08 0000007431 ARMSTRONG WORLD INDUSTRIES INC AWI 0001509566 Grizzle Victor false C/O ARMSTRONG WORLD INDUSTRIES, INC. 2500 COLUMBIA AVENUE LANCASTER PA 17603 1 1 Executive Chair 0 Common Stock 2026-04-08 4 M 0 97835 0 A 507220 D Common Stock 2026-04-08 4 F 0 42550 172.77 D 464670 D Performance Based Restricted Stock Units 2026-04-08 4 M 0 97835 0 D Common Stock 97835 0 D Reflects the conversion of previously granted performance restricted stock units into shares of Issuer's common stock in connection with the earning and payment of the units based on underlying performance metrics. Represents the number of shares withheld by the Issuer to satisfy the Reporting Person's tax obligations incurred upon the earning and payment of certain restricted stock units granted to the Reporting Person under the 2022 Equity and Cash Incentive Plan. Each performance restricted stock unit represents a contingent right to receive one share of Issuer's common stock. The performance restricted stock units were granted on March 1, 2023, under the 2022 Equity and Cash Incentive Plan of the Issuer. The performance period for the performance restricted stock units was January 1, 2023 to December 31, 2025, with the performance restricted stock units vesting at the conclusion of the performance period and earning and payment subject to achievement and certification of pre-established performance conditions. Achievement of the performance conditions was certified by the Management Development and Compensation Committee of the Board of Directors of the Issuer on April 8, 2026. Not applicable. /s/ Alan M. Kidd, Attorney-in-fact 2026-04-10