Reg FD Disclosure

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): May 8, 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 7 – Regulation FD Item 7.01 Regulation FD Disclosure. On May 8, 2025, Armstrong World Industries, Inc. (the "Company") posted an updated Investor Presentation to its website in anticipation of upcoming investor meetings. The Investor Presentation may be accessed through the “Investors” section of the Company’s website, www.armstrongceilings.com. A copy of the Investor Presentation is attached hereto as Exhibit 99.1 and incorporated herein by reference. The information in Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.1, is being furnished herewith and shall not be deemed “filed” for the purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any filing under the Act, or the Exchange Act, except as expressly set forth by specific reference in such filing. Section 9 – Financial Statements and Exhibits Item 9.01 Financial Statements and Exhibits. (d) Exhibits No. 99.1 Investor Presentation of Armstrong World Industries, Inc. dated May 8, 2025       No. 104   Cover Page Interactive Data File (embedded within the Inline XBRL document)   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   SVP General Counsel, Head of Government Relations & Chief Sustainability Officer Date: May 8, 2025   3