
Dear Fellow AZEK Stockholder: On March23, 2025, The AZEK Company Inc. (“AZEK”), James Hardie Industries plc (“James Hardie”), and Juno Merger Sub Inc., anindirect wholly owned subsidiary of James Hardie (“Merger Sub”), entered into an Agreement and Plan of Merger, as amended byAmendment No. 1 thereto, dated May 4, 2025, that provides for, among other things, the acquisition of AZEK by James Hardie. Subject toapproval by AZEK stockholders and the satisfaction or (to the extent permitted by law) waiver of certain other closing conditions, JamesHardie will acquire AZEK through the merger of Merger Sub with and into AZEK (the “merger”), with AZEK surviving the merger as anindirect wholly owned subsidiary of James Hardie. If the merger is completed, each share of AZEK class A common stock, par value $0.001 per share (“AZEK common stock”) issued andoutstanding immediately prior to the completion of the merger (other than shares held (i)by AZEK as treasury stock or directly by JamesHardie or Merger Sub and (ii) by a holder who has properly exercised and perfected (and not effectively withdrawn or lost) such holder’sdemand for appraisal rights under the General Corporation Law of the State of Delaware, the shares referred to in (i)–(-ii) collectively, the“excluded shares”) will be converted into the right to receive $26.45 in cash, without interest, and 1.0340ordinary shares of James Hardie,par value €0.59 per share (“James Hardie ordinary shares”) and, if applicable, cash in lieu of any fractional James Hardie ordinary share. James Hardie CHESS Units of Foreign Securities (“CUFS”) are listed on the Australian Stock Exchange under the symbol “JHX,” andJames Hardie American Depositary Shares (“ADSs”) are listed on the New York Stock Exchange under the symbol “JHX.” The JamesHardie ordinary shares issued in connection with the merger will be listed on the New York Stock Exchange under the symbol “JHX.”AZEK common stock is listed on the New York Stock Exchange under the symbol “AZEK.” We urge you to obtain current marketquotations for the shares of AZEK common stock and James Hardie ordinary shares. AZEK is holding a special meeting of its stockholders (the “special meeting”), at which, among other business, AZEK will ask itsstockholders to approve the adoption of the merger agreement. Information about this meeting, the merger and the other business to beconsidered by stockholders at the special meeting is contained in this proxy statement/prospectus. Any stockholder entitled to attend andvote at the special meeting is entitled to appoint a proxy to attend and vote on such stockholder’s behalf. Such proxy need not be a holderof AZEK common stock. We urge you to read this proxy statement/prospectus and the annexes and documents contained herein orincorporated by reference carefully.You should also carefully consider the risks that are described in the “Risk Factors” sectionbeginning on page25. Your vote is very important regardless of the number of shares of AZEK common stock that you own.The merger cannot becompleted without the adoption of the merger agreement by the affirmative vote of holders of a majority of the shares of AZEK commonstock outstanding and entitled to vote at the special meeting.A failure to vote your shares, or to provide instructions to your broker,bank or nominee as to how to vote your shares, is the equivalent of a vote “AGAINST” the proposal to adopt the mergeragreement. Whether or not you plan to attend the special meeting of stockholders, please submit your proxy as soon as possible to make sure that yourshares are represented at the special meeting. On behalf of the board of directors of AZEK, I thank you for your support and appreciate your consideration of these matters. Sincerely, Jesse SinghChief Executive Officer, President and Director The AZEK Company Inc. Neither the U.S. Securities and Exchange Commission nor any state securities commission has approved or disapproved of the merger orthe other transactions described in this proxy statement/prospectus or the securities to be issued in connection with the merger ordetermined if this proxy statement/prospectus is accurate or complete. Any representation to the contrary is a criminal offense. This document does not constitute a prospectus within the meaning of section 1348 of the Companies Act 2014 of Ireland (asamended) (the “Companies Act 2014”) or Article3 of the Regulation (EU) No. 2017/1129 of the European Parliament and of theCouncil of 14 June2017 (the “Prospectus Regulation”), nor a comprehensive update of information relating to the James HardieIndustries plc group. No offer of securities of James Hardie Industries plc to the public is made, or will be made, that requires thepublication of a prospectus pursuant to Irish prospectus law (within the meaning of section 1348 of the Companies Act 2014) ingeneral, or in particular pursuant to the Prospectus Regulation, the European Union (Prospectus) Regulations 2019 of I