Civil Engineering Reference
In-Depth Information
The TRADA designs (referred to in Chapter 1) showed no collar under the ridge board,
consequently for handling at the works (if the trusses are made off site), during transporta-
tion and also for on-site handling the truss is not jointed at the ridge. A temporary collar
should therefore be fitted to avoid distortion of the truss and this collar should now be
nailed into position on the rafters just below the ridge board line. On site, this will then aid
the location of the ridge board during the roof construction. The space in the setting out of
the truss to allow for the ridge board must not be varied because clearly it is vital to the
overall geometry of the truss. A thinner ridge board will mean that the truss will sag and a
thicker will result in the reverse.
The remainder of the joints in the truss can now be assembled as described above and
when all are complete all the bolts should finally be tightened before the truss is moved.
Subsequent trusses can now be assembled using the masters following the procedure de-
scribed.
