SECTION 1. Section 26A ½ of Chapter 148 of the General Laws, as appearing in the 2020 Official Edition, is hereby amended in the first paragraph by striking out the following words: “provided, further, that sprinklers shall not be required to be installed in buildings where construction has commenced prior to January first, nineteen hundred and seventy-five and which have been submitted to the provisions of chapter one hundred and eighty-three A;” and inserting in place thereof the following words:-

any building where construction has commenced prior to January 1, 1975 and which have been submitted to the provisions of chapter 183A shall comply with the following schedule for the installation of automatic sprinklers: - one-third of the gross square footage of the building or structure shall be equipped with automatic sprinklers by March 30, 2026; two-thirds of the gross square footage of the building or structure shall be equipped with automatic sprinklers by March 30, 2029; and the entire gross square footage of the building or structure shall be equipped with automatic sprinklers by March 30, 2033; provided, however, that the owner of said building or structure may apply to the board of appeals of the fire safety commission for an extension or a waiver of the provisions of this section as provided for in section 201 of chapter 6. Any building or structure subject to the provisions of this section shall have the option of complying with the following schedule: the entire gross square footage of the building or structure shall be equipped with automatic sprinklers by March 30, 2029; provided, however, that under said option the owner of said building or structure shall be deemed to have waived his right to any such extension of time.