The Episcopal campus contains a significant historic building, the Acosta-Schmidt House, built in the late 1800s. Purchased by St. Elmo W. Acosta, a influential Jacksonville businessman and City Council member, in 1911 the property included an orange grove. It then became part of the ESJ campus after the founding of the school. Its wide porch is used for numerous school events, including Commencement ceremonies. It was rededicated in 2021 in honor of Founder and Trustee Emeritus Gert H.W. Schmidt, and houses the Advancement and Alumni programs.