Quantum Consulting Engineers provided structural engineering for the historic rehabilitation of Trinity Parish Episcopal Church. John Riley first inspected Trinity Parish Episcopal Church the day following the Nisqually Earthquake in 2001 while with another firm. Home to one of the oldest congregations in Seattle, the church was severely damaged by the quake. The most obvious damage was to the bell tower, from which large stones had fallen during the quake. In addition, the upper stone transept walls had pulled away, allowing light to penetrate through a corner of the sanctuary; a brick chimney had partially collapsed and penetrated the roof; and some of the large stones shaken loose from the bell tower fell through the roof at the main entry to the sanctuary.

Bayley Construction was brought in for emergency shoring, but earthquake repair quickly turned into a major seismic upgrade and historic preservation effort, at which time Bassetti Architects joined the team. Because architectural features are directly tied to the exterior stone and backup brick, upgrading the building while preserving its beauty was a key design consideration. The design team completed the seismic upgrade without impacting the interior finishes by removing certain architectural elements such as wall finishes, select stained glass windows, and pews. After repairs and upgrades were performed, everything was returned to its place. Retrofit measures included roof truss anchorage, floor diaphragm strengthening and anchorage, new shotcrete shear walls, new footings, steel strongbacks, and sandstone and brick masonry anchorage to the new walls.

Architect: Bassetti Architects