The Massachusetts Housing Investment Corp. (MHIC) closed a $7.8 million equity investment that will help transform a historic mill into 40 affordable housing units in Leominster, Mass.

The project involves the adaptive reuse of the 118-year-old Whitney Building, which is listed on the National Register of Historic Places.

Twin Cities Community Development Corp., a nonprofit based in Fitchburg, Mass., will renovate the building to create a mix of one-, two-, three-, and four-bedroom units in addition to a management office and community space. All units will be reserved for households earning no more than 60 percent of the area median income (AMI). Eight units, which will be subsidized by Sec. 8 project-based vouchers, will be available to families earning no more than 30 percent of the AMI.

The equity investment is for the purchase of federal low-income housing tax credits and federal historic tax credits. About $6.96 million came from a MHIC multi-investor fund and $880,000 from Avidia Bank.

Other financing sources include the state Department of Housing and Community Development, the Fitchburg-Leominster HOME consortium, state historic tax credit and brownfields tax credit equity, NeighborWorks America and Department of Housing and Urban Development Economic Development Initiative grants, and energy rebates.

Davis Square Architects is the architect for the project, and Dellbrook Construction is the contractor. The project is expected to be completed in October 2012.