(1)    Definition. In this section, “eligible rehabilitation” means an improvement to housing to maintain the housing in a decent, safe, and sanitary condition or to restore it to that condition if the improvement is the removal of lead paint or constitutes a structural improvement, including any of the following:
      (a)    Repairing or replacing a heating system, electrical system, plumbing system, roof, window, or exterior door.
      (b)    Repairing the foundation.
      (c)    Repairing or replacing insulation or siding.
   (2)   Workforce housing rehabilitation loans.
234.045(2)(a) (a) From the housing rehabilitation loan fund, the authority may make a loan to a person applying for the loan to pay for the cost of eligible rehabilitation to the applicant’s home if all of the following apply:
         1.    The applicant’s household annual income does not exceed 120 percent of the area median family income for the county in which the housing is located, adjusted for family size, as published annually by the federal department of housing and urban development.
         2.    The applicant’s home is a single-family residence that the applicant occupies and that was constructed before 1980.
         3.    The applicant agrees to repay the loan, including all interest, upon the applicant selling or otherwise transferring title to the residence to another person or upon the applicant and his or her family vacating the residence.
      (b)    The authority may establish an interest rate for any loan made under par. (a) below the market interest rate or may charge no interest.