Cayman Chemical Office Building
Cayman Chemical is a biotechnology company that supplies scientists worldwide with the resources necessary for advancing human and animal health.
The company worked with Vanston/O’Brien, Inc., a general contractor and architecture firm, on the construction of a new headquarters in Pittsfield Charter Township just outside of Ann Arbor, Michigan. The L-shaped structure totaling over 66,000-square-feet of space would double as an office and laboratory research facility.
Vanston/O’Brien brought in Bluescope Conventional Steel Services (BCSS), the US-affiliate of the Australian-owned steel manufacturer based in Kansas City, Missouri, to handle structural engineering and fabrication of the steel structure. BCSS contracted with OWN, Inc. to be the structural engineer for the steel structure and to coordinate with the general contractor and the other trades involved.
The design of this 3-story conventional steel building posed a number of challenges. For starters, the building’s proximity to the local airport meant that FAA height restrictions affected the floor-to-floor clearances. Also, Michigan is in a high snow load region. When coupled with roof units and parapets, the building will see additional snow load due to drifting. Another design requirement was vibration- and floor deflection limits that would help ensure proper operation of lab equipment.
The stability of the structure was addressed with three different force resisting systems: a CMU block wall as shear wall that encased the elevator, steel chevron bracing on several exterior walls, and a large two-tier portal frame used to keep structure out of the windows.
During steel installation, the client team from Cayman Chemical changed the HVAC unit on the roof.
The new unit weighed nearly 100,000 pounds. Vanston/O’Brien contracted directly with OWN to accommodate this added load to the roof. The new challenge was to incorporate as much of the existing steel as possible by reinforcement rather than replacement. Second, by designing the reinforcement steel and connections to support the increased load. And third, by accounting for the different sized supply and return ducts unique to the new unit.
In the end, OWN went beyond to engineer a solution to accommodate the additional load while using as much of the original material as possible. This also saved Vanston/O’Brien from the hassle of finding a new engineer midstream, and helped the project stay on schedule waiting for the new HVAC unit to arrive.