STATEMENT OF PROBLEM
During design of the building steel, 4 joists in the blank receiving bay were upsized to accommodate the weight of the blank receiving air handling unit (HVU-1; 17000#) in bay 22/23, based on JEG''''s input. Later in the design phase (50% MEP design), the mechanical engineer rotated and moved the unit over one bay (to 23/24) and failed to notify the design team of the change. When it was discovered by CCC that HVU-1 design had changed, the joist steel had already been installed. A meeting was held to see if the unit could be moved back . This could not be achieved because the unit intakes were too close to high bay wall and exhaust fans, and distribution duct had already been fabricated. It was deemed less costly to reinforce existing joists.

COURSE OF ACTION
CCC contacted IBI structural to analyze the joist design to see if the joists were adequate to take the load, who then sketched the loading points for Vulcraft (the joist supplier). After Vulcraft reviewed the design, they determined that reinforcing of the joists was required in order to support the unit. CCC had Vulcraft proceed with this engineering and CCC then welded in all of the reinforcing per the Vulcraft design.

LESSON LEARNED
When steel design is underway and larger sized members are being placed in areas to support HVAC equipment, the mechanical subcontractor must agree to lock-in-place the unit locations/orientations. Any changes that must be made must effectively communicated to the team. Further, the CCC Engineering Manager must do a thorough review of all steel being installed against the latest mechanical design, prior to installation of the steel, to ensure proper matchup.