Michigan Compiled Laws, Chapter 207. Taxation § 207.557a

(a) The replacement, restoration, or construction of the facility shall be completed within 6 years of the effective date of the initial industrial facilities exemption certificate or a greater time as authorized by the commission for good cause.

(b) The commission shall provide not more than 3 separate industrial facilities exemption certificates for the facility. The initial industrial facilities exemption certificate shall be effective for not more than 14 years. The second industrial facilities exemption certificate shall be effective 2 years after the initial industrial facilities exemption certificate becomes effective and shall continue to be effective for not more than 14 years. The third industrial facilities exemption certificate shall be effective 4 years after the initial industrial facilities exemption certificate becomes effective and shall continue to be effective for not more than 14 years. The commission may modify each certificate during the replacement, restoration, or construction of the facility.

(c) For each industrial facilities exemption certificate, the commission shall determine the portion of the facility to be completed. During the first 2 years of the industrial facilities exemption certificate period, the state equalized valuation of that portion of the facility shall be used to calculate the industrial facilities tax as provided in section 14.  2 Upon the expiration of each industrial facilities exemption certificate or its revocation under section 15,  3 that portion of the facility is subject to the general ad valorem property tax.

(d) Notwithstanding subdivision (b), an industrial facilities exemption certificate for a facility described in this section shall expire not more than 12 years from the completion of the facility.