Extensive water damage from an aging roof threatened to destroy treasured artifacts housed at the McLean County Museum of History in Downtown Bloomington, IL. The water intrusion was the result of a 30-year-old, damaged roof that had exceeded its useful life span by more than five years, allowing rain to leak through the roof and insulation, clay tile and mortar down into the building’s ceilings and interior rooms.
The nationally accredited, award-winning museum occupies the former McLean County Courthouse, an American Renaissance style structure built between 1900 and 1903. The building features a limestone-clad facade and solid masonry construction with a steep sloping roof connecting the built-in gutter to the clocktower dome rising from its center. The old roof consisted of a 4-ply, built-up asphalt roof over one-inch perlite insulation mopped to the clay tile deck.