Direct Fastening Technical Guide , Edition 24
3.3.1.2 CEILING FASTENING SYSTEMS DESIGN
Figures 1 and 2 illustrate the installation of a suspended ceiling system as described in ASTM C635 . The ceiling systems shown are composed of ceiling panels which are supported by a suspension system of main runners , cross runners and wall moulding for direct hung ceiling systems . Carrying channels are part of indirect hung ceiling systems where the main runners are attached to carrying channels which are attached to concrete using Hilti ceiling fastening systems .
The entirety of the suspended ceiling system depends on the Hilti ceiling fastening hangers which support the suspension system main load carrying members . The spacing between ceiling fasteners must be determined by the design architect or engineer of record based on the loads and building code requirements or as recommended by ceiling manufacturer . Hanger wires must be wrapped by the installer to the specific requirements at the point of installation to the main runner or channel members as shown in the figures below .
The wires must be wrapped in a similar fashion at the wire hole for the X-CX ceiling clip assemblies .
Hilti ceiling fastening systems should not be used for anchorage of seismic bracing channels or compression struts . Hilti recommends the use of ICC-ES AC193 qualified mechanical anchors , such as Hilti KB-TZ , for attachment of seismic bracing for suspended ceiling systems . Reference Section 2.4 for more discussion on seismic considerations .
Hilti ceiling attachment system
Support clip for main runners
Carrying channel
Wall moulding
Cross runners Acoustical tile
Figure 1 : Indirect hung ceiling system ( reference ASTM C635 )
Spline ( spanning cross runners )
Main runners
Hilti ceiling attachment system
12 ga . wire typ .
3 tight turns in 1-1 / 2 "
Carry channel or main runner typ .
Acoustical lay-in panels
Wall moulding
Cross runners ( spanning main runners ) Figure 2 : Direct hung ceiling system ( reference ASTM C635 )
Main runners
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