County staff report mass excavation at Madison County courthouse; engineers to assess historic foundation and window protections

Madison County staff told commissioners the principal demolition phase of the county courthouse rehabilitation is finished and crews have begun mass excavation to remove the existing foundation and expand the hole toward the site of an old shed. "They're starting mass excavation to remove the existing foundation, and then they'll expand that hole back to where the old, shed was," a staff member said during the work session.

Staff framed a technical challenge: preserving historic window assemblies while achieving the protection goals that prompted discussion of ballistic-rated glazing. "The maintaining the historic windows means that they can't be properly anchored into anything because they're rather flimsy compared to what a ballistic window would be now," the staff member said, noting the county is exploring whether an 8-mil film meets protection requirements or whether storm windows integrated into new windows could be a less invasive solution.

A second staff member and the project team described newly revealed conditions adjacent to a historic foundation wall that show mortar degradation below grade. Allied (soils engineers) and a structural engineer are expected to conduct an on-site review to recommend minimally invasive, cost-effective measures to allow new pours next to the old wall. "So we'll get there. We just gotta have the engineers knock heads and come up with the best solution that's least invasive and most cost effective," a staff member said.

Commissioners were told that some historic elements above grade are sound, but below-grade footings and mortar have deteriorated after years of being covered; resolving the issue will guide next steps for foundation work and window treatment decisions. Staff said they will bring options back to the commission after the engineers' assessment.