Largo Concrete did the custom concrete formwork at the two-story, 66,074sf Sufism Reoriented Sanctuary in Walnut Creek, California. The below grade level houses the bookstore, rehearsal studios, A/V production and common areas and features a waffle slab ceiling and three grand, cast-in-place staircases leading to the ground floor. The circular design theme carried out on the ground level reflects the curvilinear form of the Sufism Emblem which has no beginning or end and represents equality as all points along the circle are equidistant from the center. The circular reception area, library and classrooms encircle the main Prayer Hall and are all crowned with 13 gently sloping concrete domes.
The largest dome over the Prayer Hall is nearly 80’ in diameter at the base and 18’ tall with a 26’ diameter oculus at the top to let natural light into the building. We used a pre-fabricated arch truss system consisting of 120 segmented ribs cut from 2x12x92” to form the large dome, each truss was flown into place resting on the lower and upper ring beam formwork. The shoring utilized a hybrid Patten Frame and Ellis Shore designed specifically to carry the unique loading characteristics of the concrete dome. The single largest and four medium sized domes were cast-in-place concrete while the other 8 utilized shotcrete application.