The Mother Church Restoration

Working closely with TFCCS, SGH evaluated the condition of the masonry facades and roofing, assisted with strategic planning, and designed a comprehensive restoration program with a 100‑year service life. Highlights of the restoration include:

Facades. SGH developed masonry repairs to address corroded embedded anchors that led to spalling and cracking in the granite and limestone facades. Our design also included reconstructing and resupporting The Mother Church Extension’s limestone balustrades on the fourth, sixth, and eighth floors, incorporating new waterproofing and flashing to mitigate leakage.

Roofs. SGH designed flat-seam metal and membrane roof replacements with flashing to address leakage at The Mother Church Extension’s setback roofs. We also designed the slate roof replacement for the Original Edifice of The Mother Church, including new flashing.

Semi-domes. The Mother Church Extension’s north and south elevations feature semi-domes that suffered from chronic leakage and deterioration. SGH designed a restoration approach to preserve and reinforce the existing interior Guastavino tiles structure by protecting the semi‑domes with new copper roofs and replicating the original exterior appearance with terra cotta rainscreens hung from custom stainless steel cable systems.

Cupola. The terra cotta-clad cupola on The Mother Church Extension’s main dome was deteriorating. SGH collaborated with the construction team to evaluate rehabilitation options with varying levels of invasiveness and service lives and helped design a replacement cupola, including new framing and terra cotta cladding. We used our field information to develop a digital model depicting the replacement steel framing, terra cotta, anchorage, and flashing that was also used by the fabricators and construction team to help them execute the work.