Multi-Phase Preservation of Historic Stone Building Underway

The multi-phase stabilization and preservation of The Stone Building, the former Augusta Mental Health Institute and Maine’s first state mental health institution, is underway. Listed on the National Register of Historic Places, the granite landmark is undergoing critical rehabilitation following nearly two decades of vacancy.

Originally constructed between 1836 and 1840 and expanded between 1848 and 1870, the Hallowell granite complex reflects 19th century institutional planning principles associated with the Kirkbride Plan, emphasizing light, ventilation and humane design. Architectural features include a two-story Greek Revival portico, later Romanesque granite additions, slate roofing and historic wood windows with stained-glass units on the primary elevation.

Closed since 2004, the building had experienced a partial roof collapse, exterior wall displacement, deteriorated slate and mortar joints and widespread window failure, leaving the structure vulnerable to ongoing water infiltration and loss of historic fabric. Phase 1 included full roof replacement, slate repair and in-kind replacement, comprehensive repointing, stone repairs and reconstruction of severely deteriorated exterior wall and gable components. The work required careful sequencing and coordination to restore structural stability while preserving the historic granite façade.

Phase 2 addressed hazardous materials abatement and selective salvage of significant interior historic woodwork in coordination with the Maine Historic Preservation Commission.

Phase 3, presently underway, includes restoration of approximately 50 historic wood windows, including original stained-glass units. Where windows are beyond repair, the team is collaborating with state preservation officials to design compatible replacement units that meet modern energy code requirements while maintaining historic proportions and minimizing long-term maintenance. The project is anticipated to be completed in March 2027.

Consulting engineering firm Gale Associates is leading the project. Benchmark is the general contractor for Phase 1 and Phase 3 (roof/walls and windows). The RC Group was the general/abatement contractor for Phase 2 (interior abatement).