Steel Deck Fastening Systems
Steel Deck Fastener Design and Selection 1.1
1.1.2.4 Fastener Inspection (Post-Fastener Installation)
Steel deck construction projects may present a challenge
with respect to the quality control of connections between
sheet steel and the supporting steel structure. Quality control
for traditional fastening methods may present a challenge
as they typically consist of visual checks and dimensional
or size verifications, which may or may not confirm a proper
fastening. Field verification of the adequacy of powder-
actuated mechanical steel deck fastenings can be conducted
as described in this section. Section 1.1.2.3). The fastener point must penetrate into,
but not necessarily through, the supporting steel (top chord
or flange), depending on the fastener/deck/base steel
configuration.
The use of mechanical fasteners does not imply a need
to inspect every fastening point unless specified by the
Structural Engineer. No guideline standards are published
by SDI, AWS, AISC or OSHA for percentages of steel
deck connections that must be checked or that can be
unsatisfactory. This determination must be made by the
Structural Engineer and Authority Having Jurisdiction. 3. Washer placement and condition. In general, the
fastener washer edges must be clamping the steel deck sheet
to the base steel. The washers should not curl upwards away
from the deck surface and must not be digging or cutting into
the steel deck surface. For the X-HSN 24 fastener, the top
hat washer must be compressed. For the X-ENP-19 fastener,
the piston mark (indentation) should be clearly visible on the
fastener washer as shown in Figure 10.
Hilti has multiple services and
aids in place that help ensure
steel deck fastenings are done
correctly the first time. Together
with a commitment to field
quality control by the steel
deck installer, these systems
may alleviate the need for post-
fastener installation inspection.
Hilti has over one thousand
Account Managers and Field
Engineers available for training
steel deck installers. This hands-
on training includes the use
of the Hilti Powder-Actuated
Tools in accordance with ANSI
Figure 9:
A10.3 safety requirements, use
Hilti Power
of the Deck Fastener Selector
Adjustment Guide
Gauge, proper steel deck layout
and end/corner lap nesting as discussed in Section 1.1.2.3.
Proper powder-actuated fastener, tool and cartridge selection
as discussed in Section 1.1.3, as well as the use of the Hilti
Power Adjustment Guide, shown in Figure 9 and discussed
in more detail in Section 1.1.3.3, are also key elements of the
installer training. Furthermore, the Hilti DX 860-HSN tools
come equipped with piston brakes, which virtually eliminate
the possibility of overdriven fasteners.
There are three main characteristics of proper fastenings that
must be considered:
1. Fasteners installed in proper locations. The fasteners
must be installed in the proper steel deck valleys or flutes in
accordance with the structural roof and floor deck plans and
design, and in the proper location in the base steel (Reference
2. Clamping of fastened part to base material.
The fasteners must clamp the steel deck down to the base
steel (top chord or flange). There should not be any visible
gaps between the steel deck and the base steel or between
steel deck laps.
Piston Mark
Figure 10: X-ENP-19 L15 Piston Mark (indentation)
When the inspector is unclear about the compression of the
top hat washer or the piston mark, the Hilti Power Adjustment
Guide may be used to measure for optimal powder-actuated
fastener nailhead stand-off, h NVS . Note that measuring nail
head stand-off does not verify proper fastener embedment
unless the steel deck and base material are tightly clamped,
with the base steel not deformed or bent. Conversely,
measuring nail head stand-off does not confirm an improper
fastening. If slightly outside the range, further investigation
into the three characteristics of proper fastenings given above
should be completed.
The following Figures 11 and 12 provide visual examples
of proper and improper steel deck fastenings for Hilti
powder-actuated bar joist (X-HSN 24) and structural steel
(X-ENP-19 L15) fasteners, respectively.
Inspection of the installed steel deck and installation of roof
coverings, insulation and membrane should be done soon
after steel deck installation to assist in alleviating corrosion
or other issues that could arise due to long-term exposure.
Fasteners must be completely protected from the weather
within 180 days after installation.
Hilti, Inc. (US) 1-800-879-8000 | www.us.hilti.com I en español 1-800-879-5000 I Hilti (Canada) Corp. 1-800-363-4458 I www.hilti.ca I PTG Decking Supplement 2014 7