Century-old cottages and modern humidity control don't always match
The nineteenth-century cottages restored during Zionsville's 1950s-60s downtown preservation effort, and more recently recognized with a March 2025 Indiana Main Street designation, were built long before central air conditioning or vapor barriers were standard — older crawlspaces and basements near the brick Main Street corridor can trap humidity in a way a newer Zionsville home never would.
Newer Zionsville construction still needs moisture management
Homes in Zionsville's newer subdivisions, built on the same Boone County glacial till and clay soil as the rest of the Carmel area, are less likely to have century-old moisture problems, but central Indiana's humid summers still make attic and crawlspace ventilation worth checking on any home regardless of age.