Fairfield's Main Street and some extensions off Main Street are designated as the Village Core Zoning District which encompasses Fairfield's Historic District.  The Historic District was entered in the National Register of Historic Places in May of 2000.

The Borough Code of Ordinances addresses some standards which are specific to the Village Core Zoning District.  In addition, any new construction and virtually any exterior alteration, renovations or remodeling at any property in the Village Core District require prior review and approval by the Fairfield Historical Architectural Review Board (HARB).  Upon approval, the HARB will recommend that Council authorize issuance of a Certificate of Appropriateness (COA).  The HARB meets monthly, as needed, on the Thursday before the monthly Borough Council meeting, which is the fourth Tuesday of each month, commencing at 7 PM.  There is no fee for HARB review or application for a COA.