Shareholder Vote · Company Update

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549     FORM 8-K     CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 12, 2025     ARMSTRONG WORLD INDUSTRIES, INC. (Exact name of registrant as specified in its charter)       Pennsylvania   1-2116   23-0366390 (State or other jurisdiction of incorporation or organization)   (Commission File Number)   (IRS Employer Identification No.)   2500 Columbia Avenue P.O. Box 3001 Lancaster , Pennsylvania   17603 (Address of principal executive offices)   (Zip Code) Registrant’s telephone number, including area code: (717) 397-0611 NA (Former name or former address if changed since last report.)     Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of   ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)   ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)   ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))   ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:   Title of each class   Trading Symbol(s)   Name of each exchange on which registered Common Stock, $0.01 par value per share   AWI   New York Stock Exchange Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐       Section 5 - Corporate Governance and Management   Item 5.07 Submission of Matters to a Vote of Security Holders. On June 12, 2025, Armstrong World Industries, Inc. (the “Company”) held its Annual Meeting of Shareholders (the “Annual Meeting”) during which shareholders: (i) elected all seven (7) nominees to the Company’s Board of Directors (the “Board”), (ii) ratified the appointment of KPMG LLP as the Company’s independent registered public accounting firm for the fiscal year 2025, and (iii) approved, on an advisory basis, the Company’s executive compensation program. The voting results are set forth in the tables below. Election of Directors        For    Withheld    Broker Non- Vote Victor D. Grizzle    39,206,215    82,228    1,413,410 Richard D. Holder    37,431,838    1,856,605    1,413,410 Barbara L. Loughran    38,203,376    1,085,067    1,413,410 William H. Osborne    37,916,340    1,372,103    1,413,410 Kathleen E. Pitre    39,206,193    82,250    1,413,410 Wayne R. Shurts    38,992,904    295,539    1,413,410 Roy W. Templin    39,163,837    124,606    1,413,410 Ratification of the Appointment of KPMG LLP   For   Against   Abstain   Broker Non-Vote 39,649,286   900,580   151,987   — Advisory Approval of Executive Compensation   For   Against   Abstain   Broker Non-Vote 33,166,629   5,968,604   153,210   1,413,410 Section 8 - Other Events   Item 8.01 Other Events. Appointment of Board Committee Members and Chairs Following the Annual Meeting, the Board appointed the following directors to be members of the Board’s standing committees, effective immediately.   Committee    Members Audit    Richard D. Holder, Barbara L. Loughran (Chair), Kathleen E. Pitre and Wayne R. Shurts Finance    Richard D. Holder, Barbara L. Loughran, and Roy W. Templin (Chair) Management Development & Compensation    William H. Osborne, Kathleen E. Pitre and Wayne R. Shurts (Chair) Nominating, Governance & Social Responsibility    Richard D. Holder (Chair), Barbara L. Loughran, and William H. Osborne     2 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.   ARMSTRONG WORLD INDUSTRIES, INC. By:   /s/ Austin K. So   Austin K. So   Senior Vice President, General Counsel, Head of Government Relations & Chief Sustainability Officer Date: June 17, 2025   3