Christ Cathedral, Garden Grove, CA

The Roman Catholic Diocese of Orange acquired the 1981 Philip Johnson Crystal Cathedral building and adjacent campus in 2012 to renovate it into the diocese’s headquarters, a “new Christ Catholic Cathedral.” The new 34-acre campus consists of seven buildings, a cemetery, residence and central chilled-water plant. Syska Hennessy Group was retained to provide MEP engineering, security, fire alarm design and high-performance building analysis services.

The project’s biggest challenge was that the existing cathedral building was naturally ventilated with only partial air conditioning. Providing full air conditioning was challenging due to limited space available for mechanical equipment, and the desire to have the most efficient HVAC system with invisible ductwork and air devices in order not to impinge on the architectural integrity of the stunning cathedral.

Syska used analytics and energy modeling, and developed various HVAC design alternatives, including underfloor, displacement ventilation and overhead, that complement and fully integrate with the architecture.

Most of the transformation is centered on the cathedral, which integrates traditional design elements and modern architecture. Daylight through the all-glass façade was used as a primary source of daylight for the sanctuary spaces. A highly efficient electric lighting system utilizing LED technology and daylight harvesting controls provides additional lighting when daylight is insufficient or additional lighting is needed to suit the special needs of the cathedral. An architectural “quatrefoil” shading system improves daylight glare conditions. Additionally, a hot-water plant was replaced as a part of the project. New HVAC systems utilize displacement ventilation to distribute cool supply air at the floor, allowing heat to stratify and rise up with air, bringing airborne contaminants up and away from people, stratifying at the top of the cathedral until being released through motorized louvers. Our strategy improved comfort, health and energy efficiency compared to typical HVAC approaches.

Syska was proud to have the opportunity to help restore and create a unique sacramental space within the framework of the original classic modern structure.