6.3 Suspended Ceiling Design Process - Bilkent University

Changes in HVAC distribution layout may create costly changes in
design; since this directly affects two high level decisions in two
systems (beam depth in structural frame system and suspended ceiling
type in suspended ceiling system). Such a loop can be avoided by
correct assumptions about floor to ceiling height, air diffuser quantity, air
diffuser layout, and HVAC and superstructure integration scheme at the
beginning of the process. The sizes of HVAC equipment may also
cause rework in plenum depth decision. In the case study, it was
reported that nearly at the end of the actual design process, the
mechanical engineer had requested a change in plenum depth due to a
change in HVAC equipment sizes and this had caused a conflict among
the participants.
Structural element connection detail is critical in determining the plenum
depth. As explained in the beginning of this chapter, generally there are
two schemes of connecting the structural elements, namely, web-to-
web and layered. In the Gürbulak case, structural members had been
connected web-to-web to save space in the plenum.
HVAC equipment and superstructure integration scheme is another
parameter that should be carefully considered in early stages of design
process, since it affects two system level upstream decisions: HVAC
distribution layout and beam depth. This parameter refers to the
decision about how structural members and HVAC ducts interact in the
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