DeAngelis Diamond Construction Inc. of Naples has started work on four area projects.

The company is building a 17,000 square-foot addition at Golden Gate Library. The structure will feature exposed concrete columns and beams, glass walls, metal trusses, a standing seam roof and interior finishes.

Magnolia Square Office Center at Goodlette-Frank roads in the Magnolia Square Office Center in Naples will serve bank building.

The Estero Fire and Rescue Administration Building is a two-story, 24,000 square foot structure includes a training facility, multipurpose community room, EMS living quarters, full kitchen and offices.

First Baptist Church of Marco Island is a 34,000 square-foot, two-story worship center, daycare and school facility located off Winterberry Road in Marco Island.