1 2 3 4 5 6 7 8
3.20
ROOF TRUSS SYSTEMS - PIGGYBACKS
Standard Details
Several TrusSteel Standard Details are available
to assist the designer in understanding and
detailing piggyback systems. These Details may
be downloaded. Detail TS003A is shown below
as an example.
Rafting
Piggyback truss systems, when properly
designed and braced, can be candidates for the
installation technique known as rafting. See
Section 7 of this manual for more information on
rafting.
Required Information
The Truss Designer will need the following
information about the roof system before
designing the piggyback system:
• all roof conditions that could require trusses
whose height will exceed the maximum
allowable truss height (candidates
for piggybacking)
• type of continuous framing / support to be
used on top of the base trusses (roof
decking/sheathing or continuous purlins)
• type of clip to be used to attach the piggyback
trusses to the base trusses or to the roof
decking/sheathing.
ENGINEERED BY ALPINE
S P E C I F Y I N G / D E S I G N I N G
